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<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedPeriodStartLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedPeriodStartLabel"/>
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/netLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/net-2009-12-16.xsd#netLabel"/>
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedNetLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedNetLabel"/>
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedTerseLabel"/>
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedPeriodEndLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedPeriodEndLabel"/>
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedLabel"/>
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedTotalLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedTotalLabel"/>
  <link:labelLink xlink:role="http://www.xbrl.org/2003/role/link" xlink:type="extended">
    <link:label id="lab_ck0000898745_S000007210Member_label_en-US" xlink:label="lab_ck0000898745_S000007210Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2050 Fund</link:label>
    <link:label id="lab_ck0000898745_S000007210Member_documentation_en-US" xlink:label="lab_ck0000898745_S000007210Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2050 Fund, S000007210</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000007210Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000007210Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000007210Member" xlink:to="lab_ck0000898745_S000007210Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000060089Member_label_en-US" xlink:label="lab_ck0000898745_S000060089Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Government Money Market Fund</link:label>
    <link:label id="lab_ck0000898745_S000060089Member_documentation_en-US" xlink:label="lab_ck0000898745_S000060089Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Government Money Market Fund S000060089Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000060089Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000060089Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000060089Member" xlink:to="lab_ck0000898745_S000060089Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000039358Member_label_en-US" xlink:label="lab_ck0000898745_C000039358Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Strategic Growth Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000039358Member_documentation_en-US" xlink:label="lab_ck0000898745_C000039358Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Strategic Growth Fund, Class R-5, C000039358, PSGFX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000039358Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000039358Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000039358Member" xlink:to="lab_ck0000898745_C000039358Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019058Member_label_en-US" xlink:label="lab_ck0000898745_C000019058Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Diversified International Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000019058Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019058Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Diversified International Fund, Class J, C000019058, PIIJX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019058Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019058Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019058Member" xlink:to="lab_ck0000898745_C000019058Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038752Member_label_en-US" xlink:label="lab_ck0000898745_C000038752Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Core Fixed Income Fund, Class A</link:label>
    <link:label id="lab_ck0000898745_C000038752Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038752Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Core Fixed Income Fund, Class A, C000038752, CMPIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038752Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038752Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038752Member" xlink:to="lab_ck0000898745_C000038752Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019782Member_label_en-US" xlink:label="lab_ck0000898745_C000019782Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Strategic Income Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000019782Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019782Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Strategic Income Fund, Institutional Class, C000019782, PLSIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019782Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019782Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019782Member" xlink:to="lab_ck0000898745_C000019782Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000190075Member_label_en-US" xlink:label="lab_ck0000898745_C000190075Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Diversified Income Fund, Class R-6</link:label>
    <link:label id="lab_ck0000898745_C000190075Member_documentation_en-US" xlink:label="lab_ck0000898745_C000190075Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Diversified Income Fund, Class R-6</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000190075Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000190075Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000190075Member" xlink:to="lab_ck0000898745_C000190075Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000063447Member_label_en-US" xlink:label="lab_ck0000898745_C000063447Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2055 Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000063447Member_documentation_en-US" xlink:label="lab_ck0000898745_C000063447Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2055 Fund, Class R-3, C000063447, LTFDX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000063447Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000063447Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000063447Member" xlink:to="lab_ck0000898745_C000063447Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019332Member_label_en-US" xlink:label="lab_ck0000898745_C000019332Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">LargeCap Growth Fund I, Class J</link:label>
    <link:label id="lab_ck0000898745_C000019332Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019332Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">LargeCap Growth I Fund, Class J, C000019332, PLGJX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019332Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019332Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019332Member" xlink:to="lab_ck0000898745_C000019332Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019372Member_label_en-US" xlink:label="lab_ck0000898745_C000019372Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">International Equity Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000019372Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019372Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">International Equity Fund, Class R-3, C000019372, PRPPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019372Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019372Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019372Member" xlink:to="lab_ck0000898745_C000019372Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_DerivativesRiskOptionsRiskMember_label_en-US" xlink:label="lab_ck0000898745_DerivativesRiskOptionsRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Derivatives Risk, Options Risk Member</link:label>
    <link:label id="lab_ck0000898745_DerivativesRiskOptionsRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_DerivativesRiskOptionsRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Derivatives Risk, Options Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_DerivativesRiskOptionsRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_DerivativesRiskOptionsRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_DerivativesRiskOptionsRiskMember" xlink:to="lab_ck0000898745_DerivativesRiskOptionsRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019742Member_label_en-US" xlink:label="lab_ck0000898745_C000019742Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2020 Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000019742Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019742Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2020 Fund, Class R-3, C000019742, PTBMX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019742Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019742Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019742Member" xlink:to="lab_ck0000898745_C000019742Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000199316Member_label_en-US" xlink:label="lab_ck0000898745_C000199316Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2055 Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000199316Member_documentation_en-US" xlink:label="lab_ck0000898745_C000199316Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2055 Fund, Class J, C000199316</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000199316Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000199316Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000199316Member" xlink:to="lab_ck0000898745_C000199316Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000145332Member_label_en-US" xlink:label="lab_ck0000898745_C000145332Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2050 Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000145332Member_documentation_en-US" xlink:label="lab_ck0000898745_C000145332Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2050 Fund, Institutional Class, C000145332, PHTUX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000145332Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000145332Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000145332Member" xlink:to="lab_ck0000898745_C000145332Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000039353Member_label_en-US" xlink:label="lab_ck0000898745_C000039353Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Flexible Income Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000039353Member_documentation_en-US" xlink:label="lab_ck0000898745_C000039353Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Flexible Income Fund, Class J, C000039353, PFIJX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000039353Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000039353Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000039353Member" xlink:to="lab_ck0000898745_C000039353Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000007081Member_label_en-US" xlink:label="lab_ck0000898745_S000007081Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Money Market Fund</link:label>
    <link:label id="lab_ck0000898745_S000007081Member_documentation_en-US" xlink:label="lab_ck0000898745_S000007081Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Money Market Fund, S000007081</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000007081Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000007081Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000007081Member" xlink:to="lab_ck0000898745_S000007081Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000046559Member_label_en-US" xlink:label="lab_ck0000898745_S000046559Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2030 Fund</link:label>
    <link:label id="lab_ck0000898745_S000046559Member_documentation_en-US" xlink:label="lab_ck0000898745_S000046559Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2030 Fund, S000046559</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000046559Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000046559Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000046559Member" xlink:to="lab_ck0000898745_S000046559Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019085Member_label_en-US" xlink:label="lab_ck0000898745_C000019085Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inflation Protection Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000019085Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019085Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Inflation Protection Fund, Class J, C000019085, PIPJX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019085Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019085Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019085Member" xlink:to="lab_ck0000898745_C000019085Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038760Member_label_en-US" xlink:label="lab_ck0000898745_C000038760Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Government &amp; High Quality Bond Fund, Class A</link:label>
    <link:label id="lab_ck0000898745_C000038760Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038760Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Government &amp; High Quality Bond Fund, Class A, C000038760, CMPGX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038760Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038760Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038760Member" xlink:to="lab_ck0000898745_C000038760Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019586Member_label_en-US" xlink:label="lab_ck0000898745_C000019586Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SmallCap Value II Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000019586Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019586Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SmallCap Value II Fund, Class R-5, C000019586, PLARX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019586Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019586Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019586Member" xlink:to="lab_ck0000898745_C000019586Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000007075Member_label_en-US" xlink:label="lab_ck0000898745_S000007075Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MidCap Fund</link:label>
    <link:label id="lab_ck0000898745_S000007075Member_documentation_en-US" xlink:label="lab_ck0000898745_S000007075Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MidCap Fund f/k/a Midcap Blend, S000007075</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000007075Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000007075Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000007075Member" xlink:to="lab_ck0000898745_S000007075Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019774Member_label_en-US" xlink:label="lab_ck0000898745_C000019774Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2050 Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000019774Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019774Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2050 Fund, Class J, C000019774, PFLJX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019774Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019774Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019774Member" xlink:to="lab_ck0000898745_C000019774Member" xlink:type="arc" order="1"/>
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    <link:label id="lab_ck0000898745_C000085762Member_documentation_en-US" xlink:label="lab_ck0000898745_C000085762Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal Capital Appreciation Fund, Class R-5 Shares, C000085762, PCAQX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000085762Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000085762Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000085762Member" xlink:to="lab_ck0000898745_C000085762Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038717Member_label_en-US" xlink:label="lab_ck0000898745_C000038717Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">California Municipal Fund, Class C</link:label>
    <link:label id="lab_ck0000898745_C000038717Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038717Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">California Municipal Fund, Class C, C000038717, SRCCX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038717Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038717Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038717Member" xlink:to="lab_ck0000898745_C000038717Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_SAMConservativeBalancedBlendedIndexExceptAsNotedForMSCIEAFEIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_SAMConservativeBalancedBlendedIndexExceptAsNotedForMSCIEAFEIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Conservative Balanced Blended Index (except as noted for MSCI EAFE Index NTR, reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_SAMConservativeBalancedBlendedIndexExceptAsNotedForMSCIEAFEIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_SAMConservativeBalancedBlendedIndexExceptAsNotedForMSCIEAFEIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Conservative Balanced Blended Index (except as noted for MSCI EAFE Index NTR, reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_SAMConservativeBalancedBlendedIndexExceptAsNotedForMSCIEAFEIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_SAMConservativeBalancedBlendedIndexExceptAsNotedForMSCIEAFEIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_SAMConservativeBalancedBlendedIndexExceptAsNotedForMSCIEAFEIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:to="lab_ck0000898745_SAMConservativeBalancedBlendedIndexExceptAsNotedForMSCIEAFEIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_SPTargetDate2030IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_SPTargetDate2030IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">S&amp;P Target Date 2030 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_SPTargetDate2030IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_SPTargetDate2030IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">S&amp;P Target Date 2030 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_SPTargetDate2030IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_SPTargetDate2030IndexreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_SPTargetDate2030IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0000898745_SPTargetDate2030IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_SPTargetDate2050IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_SPTargetDate2050IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">S&amp;P Target Date 2050 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_SPTargetDate2050IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_SPTargetDate2050IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">S&amp;P Target Date 2050 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_SPTargetDate2050IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_SPTargetDate2050IndexreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_SPTargetDate2050IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0000898745_SPTargetDate2050IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000046560Member_label_en-US" xlink:label="lab_ck0000898745_S000046560Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2035 Fund</link:label>
    <link:label id="lab_ck0000898745_S000046560Member_documentation_en-US" xlink:label="lab_ck0000898745_S000046560Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2035 Fund, S000046560</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000046560Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000046560Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000046560Member" xlink:to="lab_ck0000898745_S000046560Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_MSCIEmergingMarketsIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_MSCIEmergingMarketsIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MSCI Emerging Markets Index NTR (reflects withholding taxes on foreign dividends, but no deduction for fees, expenses, or other taxes)</link:label>
    <link:label id="lab_ck0000898745_MSCIEmergingMarketsIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_MSCIEmergingMarketsIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MSCI Emerging Markets Index NTR (reflects withholding taxes on foreign dividends, but no deduction for fees, expenses, or other taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_MSCIEmergingMarketsIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_MSCIEmergingMarketsIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_MSCIEmergingMarketsIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember" xlink:to="lab_ck0000898745_MSCIEmergingMarketsIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038744Member_label_en-US" xlink:label="lab_ck0000898745_C000038744Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equity Income Fund, Class A</link:label>
    <link:label id="lab_ck0000898745_C000038744Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038744Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Equity Income Fund, Class A, C000038744, PQIAX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038744Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038744Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038744Member" xlink:to="lab_ck0000898745_C000038744Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000113844Member_label_en-US" xlink:label="lab_ck0000898745_C000113844Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Government &amp; High Quality Bond Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000113844Member_documentation_en-US" xlink:label="lab_ck0000898745_C000113844Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Government &amp; High Quality Bond Fund, Class R-5, C00113844, PMREX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000113844Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000113844Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000113844Member" xlink:to="lab_ck0000898745_C000113844Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019790Member_label_en-US" xlink:label="lab_ck0000898745_C000019790Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Real Estate Securities Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000019790Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019790Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Real Estate Securities, Institutional Class, C000019790, PIREX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019790Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019790Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019790Member" xlink:to="lab_ck0000898745_C000019790Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000058848Member_label_en-US" xlink:label="lab_ck0000898745_S000058848Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2065 Fund</link:label>
    <link:label id="lab_ck0000898745_S000058848Member_documentation_en-US" xlink:label="lab_ck0000898745_S000058848Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2065 S000058848</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000058848Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000058848Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000058848Member" xlink:to="lab_ck0000898745_S000058848Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019755Member_label_en-US" xlink:label="lab_ck0000898745_C000019755Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2030 Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000019755Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019755Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2030 Fund, Class J, C000019755, PLTJX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019755Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019755Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019755Member" xlink:to="lab_ck0000898745_C000019755Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000039337Member_label_en-US" xlink:label="lab_ck0000898745_C000039337Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Conservative Balanced Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000039337Member_documentation_en-US" xlink:label="lab_ck0000898745_C000039337Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Conservative Balanced Fund, Class R-3, C000039337, PCBPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000039337Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000039337Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000039337Member" xlink:to="lab_ck0000898745_C000039337Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019142Member_label_en-US" xlink:label="lab_ck0000898745_C000019142Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Global Emerging Markets Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000019142Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019142Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Global Emerging Markets Fund, Class R-5, C000019142, PEPSX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019142Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019142Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019142Member" xlink:to="lab_ck0000898745_C000019142Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_BloombergUSCorporateHighYieldTwoPercentIssuerCappedIndexreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_BloombergUSCorporateHighYieldTwoPercentIssuerCappedIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Bloomberg U.S. Corporate High Yield 2% Issuer Capped Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_BloombergUSCorporateHighYieldTwoPercentIssuerCappedIndexreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_BloombergUSCorporateHighYieldTwoPercentIssuerCappedIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Bloomberg U.S. Corporate High Yield 2% Issuer Capped Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_BloombergUSCorporateHighYieldTwoPercentIssuerCappedIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_BloombergUSCorporateHighYieldTwoPercentIssuerCappedIndexreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_BloombergUSCorporateHighYieldTwoPercentIssuerCappedIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0000898745_BloombergUSCorporateHighYieldTwoPercentIssuerCappedIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000158782Member_label_en-US" xlink:label="lab_ck0000898745_C000158782Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Tax-Exempt Bond Fund, Institutional</link:label>
    <link:label id="lab_ck0000898745_C000158782Member_documentation_en-US" xlink:label="lab_ck0000898745_C000158782Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Tax-Exempt Bond Fund, Institutional</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000158782Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000158782Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000158782Member" xlink:to="lab_ck0000898745_C000158782Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_MSCIEAFEValueIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_MSCIEAFEValueIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MSCI EAFE Value Index NTR (reflects withholding taxes on foreign dividends, but no deduction for fees, expenses, or other taxes)</link:label>
    <link:label id="lab_ck0000898745_MSCIEAFEValueIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_MSCIEAFEValueIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MSCI EAFE Value Index NTR (reflects withholding taxes on foreign dividends, but no deduction for fees, expenses, or other taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_MSCIEAFEValueIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_MSCIEAFEValueIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_MSCIEAFEValueIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember" xlink:to="lab_ck0000898745_MSCIEAFEValueIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000159890Member_label_en-US" xlink:label="lab_ck0000898745_C000159890Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2030 Fund, R-6</link:label>
    <link:label id="lab_ck0000898745_C000159890Member_documentation_en-US" xlink:label="lab_ck0000898745_C000159890Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2030 Fund, C000159890, R-6</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000159890Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000159890Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000159890Member" xlink:to="lab_ck0000898745_C000159890Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019345Member_label_en-US" xlink:label="lab_ck0000898745_C000019345Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MidCap S&amp;P 400 Index Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000019345Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019345Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MidCap S&amp;P 400 Index Fund, Class R-3, C000019345, PMFMX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019345Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019345Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019345Member" xlink:to="lab_ck0000898745_C000019345Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019316Member_label_en-US" xlink:label="lab_ck0000898745_C000019316Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MidCap Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000019316Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019316Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MidCap Fund, Class J, C000019316, PMBJX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019316Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019316Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019316Member" xlink:to="lab_ck0000898745_C000019316Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038733Member_label_en-US" xlink:label="lab_ck0000898745_C000038733Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Strategic Growth Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000038733Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038733Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Strategic Growth Fund, Institutional Class, C000038733, PSWIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038733Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038733Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038733Member" xlink:to="lab_ck0000898745_C000038733Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019761Member_label_en-US" xlink:label="lab_ck0000898745_C000019761Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2040 Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000019761Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019761Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2040 Fund, Class R-5, C000019761, PTDPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019761Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019761Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019761Member" xlink:to="lab_ck0000898745_C000019761Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000046554Member_label_en-US" xlink:label="lab_ck0000898745_S000046554Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2055 Fund</link:label>
    <link:label id="lab_ck0000898745_S000046554Member_documentation_en-US" xlink:label="lab_ck0000898745_S000046554Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2055 Fund, S000046554</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000046554Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000046554Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000046554Member" xlink:to="lab_ck0000898745_S000046554Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000007209Member_label_en-US" xlink:label="lab_ck0000898745_S000007209Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2040 Fund</link:label>
    <link:label id="lab_ck0000898745_S000007209Member_documentation_en-US" xlink:label="lab_ck0000898745_S000007209Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2040 Fund, S000007209</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000007209Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000007209Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000007209Member" xlink:to="lab_ck0000898745_S000007209Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_FloatingAndVariableRateSecuritiesRiskMember_label_en-US" xlink:label="lab_ck0000898745_FloatingAndVariableRateSecuritiesRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Floating And Variable Rate Securities Risk Member</link:label>
    <link:label id="lab_ck0000898745_FloatingAndVariableRateSecuritiesRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_FloatingAndVariableRateSecuritiesRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Floating And Variable Rate Securities Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_FloatingAndVariableRateSecuritiesRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_FloatingAndVariableRateSecuritiesRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_FloatingAndVariableRateSecuritiesRiskMember" xlink:to="lab_ck0000898745_FloatingAndVariableRateSecuritiesRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_HedgingRiskMember_label_en-US" xlink:label="lab_ck0000898745_HedgingRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Hedging Risk Member</link:label>
    <link:label id="lab_ck0000898745_HedgingRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_HedgingRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Hedging Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_HedgingRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_HedgingRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_HedgingRiskMember" xlink:to="lab_ck0000898745_HedgingRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000063439Member_label_en-US" xlink:label="lab_ck0000898745_C000063439Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2035 Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000063439Member_documentation_en-US" xlink:label="lab_ck0000898745_C000063439Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2035 Fund, Institutional Class, C000063439, LTIUX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000063439Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000063439Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000063439Member" xlink:to="lab_ck0000898745_C000063439Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019779Member_label_en-US" xlink:label="lab_ck0000898745_C000019779Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Strategic Income Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000019779Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019779Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Strategic Income Fund, Class R-3, C000019779, PLSMX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019779Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019779Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019779Member" xlink:to="lab_ck0000898745_C000019779Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000076718Member_label_en-US" xlink:label="lab_ck0000898745_C000076718Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MidCap Value I Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000076718Member_documentation_en-US" xlink:label="lab_ck0000898745_C000076718Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MidCap Value I Fund, Class J, C000076718, PVEJX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000076718Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000076718Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000076718Member" xlink:to="lab_ck0000898745_C000076718Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019461Member_label_en-US" xlink:label="lab_ck0000898745_C000019461Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">LargeCap Value Fund III, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000019461Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019461Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">LargeCap Value III Fund, Class R-5, C000019461, PPSRX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019461Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019461Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019461Member" xlink:to="lab_ck0000898745_C000019461Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019618Member_label_en-US" xlink:label="lab_ck0000898745_C000019618Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MidCap Value I Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000019618Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019618Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MidCap Value I Fund, Institutional Class, C000019618, PVMIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019618Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019618Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019618Member" xlink:to="lab_ck0000898745_C000019618Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000007207Member_label_en-US" xlink:label="lab_ck0000898745_S000007207Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2020 Fund</link:label>
    <link:label id="lab_ck0000898745_S000007207Member_documentation_en-US" xlink:label="lab_ck0000898745_S000007207Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2020 Fund, S000007207</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000007207Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000007207Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000007207Member" xlink:to="lab_ck0000898745_S000007207Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000085767Member_label_en-US" xlink:label="lab_ck0000898745_C000085767Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equity Income Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000085767Member_documentation_en-US" xlink:label="lab_ck0000898745_C000085767Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Equity Income Fund, Class R-5 Shares, C000085767, PEIQX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000085767Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000085767Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000085767Member" xlink:to="lab_ck0000898745_C000085767Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000014236Member_label_en-US" xlink:label="lab_ck0000898745_S000014236Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Strategic Asset Management Strategic Growth Portfolio</link:label>
    <link:label id="lab_ck0000898745_S000014236Member_documentation_en-US" xlink:label="lab_ck0000898745_S000014236Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Strategic Asset Management Strategic Growth Portfolio, S000014236</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000014236Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000014236Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000014236Member" xlink:to="lab_ck0000898745_S000014236Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000014246Member_label_en-US" xlink:label="lab_ck0000898745_S000014246Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Strategic Asset Management Balanced Portfolio</link:label>
    <link:label id="lab_ck0000898745_S000014246Member_documentation_en-US" xlink:label="lab_ck0000898745_S000014246Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Strategic Asset Management Balanced Portfolio, S000014246</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000014246Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000014246Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000014246Member" xlink:to="lab_ck0000898745_S000014246Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000113842Member_label_en-US" xlink:label="lab_ck0000898745_C000113842Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Government &amp; High Quality Bond Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000113842Member_documentation_en-US" xlink:label="lab_ck0000898745_C000113842Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Government &amp; High Quality Bond Fund, Class R-3, C000113842, PRCMX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000113842Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000113842Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000113842Member" xlink:to="lab_ck0000898745_C000113842Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000039364Member_label_en-US" xlink:label="lab_ck0000898745_C000039364Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Balanced Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000039364Member_documentation_en-US" xlink:label="lab_ck0000898745_C000039364Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Balanced Fund, Class R-5, C000039364, PSBFX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000039364Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000039364Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000039364Member" xlink:to="lab_ck0000898745_C000039364Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_RussellMidCapIndexreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_RussellMidCapIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Russell MidCap Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_RussellMidCapIndexreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_RussellMidCapIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Russell MidCap Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_RussellMidCapIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_RussellMidCapIndexreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_RussellMidCapIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0000898745_RussellMidCapIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038771Member_label_en-US" xlink:label="lab_ck0000898745_C000038771Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Balanced Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000038771Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038771Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Balanced Fund, Institutional Class, C000038771, PSBIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038771Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038771Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038771Member" xlink:to="lab_ck0000898745_C000038771Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_BloombergUSAggregateIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_BloombergUSAggregateIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Bloomberg US Aggregate Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_BloombergUSAggregateIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_BloombergUSAggregateIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Bloomberg US Aggregate Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_BloombergUSAggregateIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_BloombergUSAggregateIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_BloombergUSAggregateIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:to="lab_ck0000898745_BloombergUSAggregateIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000175488Member_label_en-US" xlink:label="lab_ck0000898745_C000175488Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">High Yield Fund, Class R-6</link:label>
    <link:label id="lab_ck0000898745_C000175488Member_documentation_en-US" xlink:label="lab_ck0000898745_C000175488Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">High Yield Fund, Class R-6, C000175488</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000175488Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000175488Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000175488Member" xlink:to="lab_ck0000898745_C000175488Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000199324Member_label_en-US" xlink:label="lab_ck0000898745_C000199324Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2045 Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000199324Member_documentation_en-US" xlink:label="lab_ck0000898745_C000199324Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2045 Fund, Class J, C000199324</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000199324Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000199324Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000199324Member" xlink:to="lab_ck0000898745_C000199324Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_PortfolioDurationRiskMember_label_en-US" xlink:label="lab_ck0000898745_PortfolioDurationRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Portfolio Duration Risk Member</link:label>
    <link:label id="lab_ck0000898745_PortfolioDurationRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_PortfolioDurationRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Portfolio Duration Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_PortfolioDurationRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_PortfolioDurationRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_PortfolioDurationRiskMember" xlink:to="lab_ck0000898745_PortfolioDurationRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019630Member_label_en-US" xlink:label="lab_ck0000898745_C000019630Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SmallCap Growth I Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000019630Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019630Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SmallCap Growth I Fund, Institutional Class, C000019630, PGRTX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019630Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019630Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019630Member" xlink:to="lab_ck0000898745_C000019630Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000123727Member_label_en-US" xlink:label="lab_ck0000898745_C000123727Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2060 Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000123727Member_documentation_en-US" xlink:label="lab_ck0000898745_C000123727Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2060 Fund, Institutional Class, C000123727</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000123727Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000123727Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000123727Member" xlink:to="lab_ck0000898745_C000123727Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019763Member_label_en-US" xlink:label="lab_ck0000898745_C000019763Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2040 Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000019763Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019763Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2040 Fund, Institutional Class, C000019763, PTDIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019763Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019763Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019763Member" xlink:to="lab_ck0000898745_C000019763Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000153061Member_label_en-US" xlink:label="lab_ck0000898745_C000153061Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">California Municipal Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000153061Member_documentation_en-US" xlink:label="lab_ck0000898745_C000153061Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">California Municipal Fund, Institutional Class, C000153061</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000153061Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000153061Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000153061Member" xlink:to="lab_ck0000898745_C000153061Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_IndexFundRiskMember_label_en-US" xlink:label="lab_ck0000898745_IndexFundRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Index Fund Risk Member</link:label>
    <link:label id="lab_ck0000898745_IndexFundRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_IndexFundRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Index Fund Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_IndexFundRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_IndexFundRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_IndexFundRiskMember" xlink:to="lab_ck0000898745_IndexFundRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_IndustryConcentrationRiskRealEstateRiskMember_label_en-US" xlink:label="lab_ck0000898745_IndustryConcentrationRiskRealEstateRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Industry Concentration Risk, Real Estate Risk Member</link:label>
    <link:label id="lab_ck0000898745_IndustryConcentrationRiskRealEstateRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_IndustryConcentrationRiskRealEstateRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Industry Concentration Risk, Real Estate Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_IndustryConcentrationRiskRealEstateRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_IndustryConcentrationRiskRealEstateRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_IndustryConcentrationRiskRealEstateRiskMember" xlink:to="lab_ck0000898745_IndustryConcentrationRiskRealEstateRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000039873Member_label_en-US" xlink:label="lab_ck0000898745_S000039873Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2060 Fund</link:label>
    <link:label id="lab_ck0000898745_S000039873Member_documentation_en-US" xlink:label="lab_ck0000898745_S000039873Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2060 Fund, S000039873</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000039873Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000039873Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000039873Member" xlink:to="lab_ck0000898745_S000039873Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019771Member_label_en-US" xlink:label="lab_ck0000898745_C000019771Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2050 Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000019771Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019771Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2050 Fund, Class R-5, C000019771, PTEFX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019771Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019771Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019771Member" xlink:to="lab_ck0000898745_C000019771Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000007169Member_label_en-US" xlink:label="lab_ck0000898745_S000007169Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SmallCap Value Fund II</link:label>
    <link:label id="lab_ck0000898745_S000007169Member_documentation_en-US" xlink:label="lab_ck0000898745_S000007169Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SmallCap Value Fund II, S000007169</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000007169Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000007169Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000007169Member" xlink:to="lab_ck0000898745_S000007169Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038763Member_label_en-US" xlink:label="lab_ck0000898745_C000038763Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Government &amp; High Quality Bond Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000038763Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038763Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Government &amp; High Quality Bond Fund, Institutional Class, C000038763, PMRIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038763Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038763Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038763Member" xlink:to="lab_ck0000898745_C000038763Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000007016Member_label_en-US" xlink:label="lab_ck0000898745_S000007016Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">LargeCap S&amp;P 500 Index Fund</link:label>
    <link:label id="lab_ck0000898745_S000007016Member_documentation_en-US" xlink:label="lab_ck0000898745_S000007016Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">LargeCap S&amp;P 500 Index Fund, S000007016</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000007016Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000007016Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000007016Member" xlink:to="lab_ck0000898745_S000007016Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000039361Member_label_en-US" xlink:label="lab_ck0000898745_C000039361Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Balanced Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000039361Member_documentation_en-US" xlink:label="lab_ck0000898745_C000039361Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Balanced Fund, Class R-3, C000039361, PBAPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000039361Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000039361Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000039361Member" xlink:to="lab_ck0000898745_C000039361Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_SAMBalancedBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_SAMBalancedBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Balanced Blended Index (except as noted for MSCI ACWI Index NTR, reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_SAMBalancedBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_SAMBalancedBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Balanced Blended Index (except as noted for MSCI ACWI Index NTR, reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_SAMBalancedBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_SAMBalancedBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_SAMBalancedBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:to="lab_ck0000898745_SAMBalancedBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038720Member_label_en-US" xlink:label="lab_ck0000898745_C000038720Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Conservative Balanced Fund, Class C</link:label>
    <link:label id="lab_ck0000898745_C000038720Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038720Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Conservative Balanced Fund, Class C, C000038720, SCIPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038720Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038720Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038720Member" xlink:to="lab_ck0000898745_C000038720Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_VolatilityMitigationRiskMember_label_en-US" xlink:label="lab_ck0000898745_VolatilityMitigationRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Volatility Mitigation Risk Member</link:label>
    <link:label id="lab_ck0000898745_VolatilityMitigationRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_VolatilityMitigationRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Volatility Mitigation Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_VolatilityMitigationRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_VolatilityMitigationRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_VolatilityMitigationRiskMember" xlink:to="lab_ck0000898745_VolatilityMitigationRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019348Member_label_en-US" xlink:label="lab_ck0000898745_C000019348Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MidCap S&amp;P 400 Index Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000019348Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019348Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MidCap S&amp;P 400 Index Fund, Class J, C000019348, PMFJX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019348Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019348Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019348Member" xlink:to="lab_ck0000898745_C000019348Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000014244Member_label_en-US" xlink:label="lab_ck0000898745_S000014244Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Government &amp; High Quality Bond Fund</link:label>
    <link:label id="lab_ck0000898745_S000014244Member_documentation_en-US" xlink:label="lab_ck0000898745_S000014244Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Government &amp; High Quality Bond Fund f/k/a Mortgage Securities Fund, S000014244</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000014244Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000014244Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000014244Member" xlink:to="lab_ck0000898745_S000014244Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_HighPortfolioTurnoverRiskMember_label_en-US" xlink:label="lab_ck0000898745_HighPortfolioTurnoverRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">High Portfolio Turnover Risk Member</link:label>
    <link:label id="lab_ck0000898745_HighPortfolioTurnoverRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_HighPortfolioTurnoverRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">High Portfolio Turnover Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_HighPortfolioTurnoverRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_HighPortfolioTurnoverRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_HighPortfolioTurnoverRiskMember" xlink:to="lab_ck0000898745_HighPortfolioTurnoverRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_InverseFloatingRateInvestmentsRiskMember_label_en-US" xlink:label="lab_ck0000898745_InverseFloatingRateInvestmentsRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inverse Floating Rate Investments Risk Member</link:label>
    <link:label id="lab_ck0000898745_InverseFloatingRateInvestmentsRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_InverseFloatingRateInvestmentsRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Inverse Floating Rate Investments Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_InverseFloatingRateInvestmentsRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_InverseFloatingRateInvestmentsRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_InverseFloatingRateInvestmentsRiskMember" xlink:to="lab_ck0000898745_InverseFloatingRateInvestmentsRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_SPTargetDate2040IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_SPTargetDate2040IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">S&amp;P Target Date 2040 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_SPTargetDate2040IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_SPTargetDate2040IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">S&amp;P Target Date 2040 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_SPTargetDate2040IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_SPTargetDate2040IndexreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_SPTargetDate2040IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0000898745_SPTargetDate2040IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000199322Member_label_en-US" xlink:label="lab_ck0000898745_C000199322Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2035 Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000199322Member_documentation_en-US" xlink:label="lab_ck0000898745_C000199322Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2035 Fund, Class J, C000199322</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000199322Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000199322Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000199322Member" xlink:to="lab_ck0000898745_C000199322Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000007212Member_label_en-US" xlink:label="lab_ck0000898745_S000007212Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Real Estate Securities Fund</link:label>
    <link:label id="lab_ck0000898745_S000007212Member_documentation_en-US" xlink:label="lab_ck0000898745_S000007212Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Real Estate Securities Fund, S000007212</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000007212Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000007212Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000007212Member" xlink:to="lab_ck0000898745_S000007212Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_JPMEMBlendWeightIndexMember_label_en-US" xlink:label="lab_ck0000898745_JPMEMBlendWeightIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">JPM EM Blend Weight Index</link:label>
    <link:label id="lab_ck0000898745_JPMEMBlendWeightIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_JPMEMBlendWeightIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">JPM EM Blend Weight Index</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_JPMEMBlendWeightIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_JPMEMBlendWeightIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_JPMEMBlendWeightIndexMember" xlink:to="lab_ck0000898745_JPMEMBlendWeightIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000199319Member_label_en-US" xlink:label="lab_ck0000898745_C000199319Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2020 Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000199319Member_documentation_en-US" xlink:label="lab_ck0000898745_C000199319Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2020 Fund, Class J, C000199319</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000199319Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000199319Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000199319Member" xlink:to="lab_ck0000898745_C000199319Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000024296Member_label_en-US" xlink:label="lab_ck0000898745_S000024296Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Diversified Income Fund</link:label>
    <link:label id="lab_ck0000898745_S000024296Member_documentation_en-US" xlink:label="lab_ck0000898745_S000024296Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Diversified Income Fund, S000024296</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000024296Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000024296Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000024296Member" xlink:to="lab_ck0000898745_S000024296Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_SPTargetDate2045IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_SPTargetDate2045IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">S&amp;P Target Date 2045 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_SPTargetDate2045IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_SPTargetDate2045IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">S&amp;P Target Date 2045 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_SPTargetDate2045IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_SPTargetDate2045IndexreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_SPTargetDate2045IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0000898745_SPTargetDate2045IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_LeverageRiskMember_label_en-US" xlink:label="lab_ck0000898745_LeverageRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Leverage Risk Member</link:label>
    <link:label id="lab_ck0000898745_LeverageRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_LeverageRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Leverage Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_LeverageRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_LeverageRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_LeverageRiskMember" xlink:to="lab_ck0000898745_LeverageRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_RealEstateSecuritiesRiskMember_label_en-US" xlink:label="lab_ck0000898745_RealEstateSecuritiesRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Real Estate Securities Risk Member</link:label>
    <link:label id="lab_ck0000898745_RealEstateSecuritiesRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_RealEstateSecuritiesRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Real Estate Securities Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_RealEstateSecuritiesRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_RealEstateSecuritiesRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_RealEstateSecuritiesRiskMember" xlink:to="lab_ck0000898745_RealEstateSecuritiesRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000039340Member_label_en-US" xlink:label="lab_ck0000898745_C000039340Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Conservative Balanced Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000039340Member_documentation_en-US" xlink:label="lab_ck0000898745_C000039340Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Conservative Balanced Fund, Class R-5, C000039340, PCBFX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000039340Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000039340Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000039340Member" xlink:to="lab_ck0000898745_C000039340Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_SandPSmallcap600ReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_SandPSmallcap600ReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">S&amp;P SmallCap 600 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_SandPSmallcap600ReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_SandPSmallcap600ReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">S&amp;P SmallCap 600 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_SandPSmallcap600ReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_SandPSmallcap600ReflectsNoDeductionForFeesExpensesOrTaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_SandPSmallcap600ReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:to="lab_ck0000898745_SandPSmallcap600ReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000052887Member_label_en-US" xlink:label="lab_ck0000898745_C000052887Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Global Real Estate Securities Fund, Class A</link:label>
    <link:label id="lab_ck0000898745_C000052887Member_documentation_en-US" xlink:label="lab_ck0000898745_C000052887Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Global Real Estate Securities Fund, Class A, C000052887, POSAX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000052887Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000052887Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000052887Member" xlink:to="lab_ck0000898745_C000052887Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_DiscretionaryLiquidityFeeRiskMember_label_en-US" xlink:label="lab_ck0000898745_DiscretionaryLiquidityFeeRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Discretionary Liquidity Fee Risk Member</link:label>
    <link:label id="lab_ck0000898745_DiscretionaryLiquidityFeeRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_DiscretionaryLiquidityFeeRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Discretionary Liquidity Fee Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_DiscretionaryLiquidityFeeRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_DiscretionaryLiquidityFeeRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_DiscretionaryLiquidityFeeRiskMember" xlink:to="lab_ck0000898745_DiscretionaryLiquidityFeeRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038736Member_label_en-US" xlink:label="lab_ck0000898745_C000038736Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Tax-Exempt Bond Fund, Class C</link:label>
    <link:label id="lab_ck0000898745_C000038736Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038736Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Tax-Exempt Bond Fund, Class C, C000038736, PTBCX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038736Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038736Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038736Member" xlink:to="lab_ck0000898745_C000038736Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_SecuritizedProductsRiskMember_label_en-US" xlink:label="lab_ck0000898745_SecuritizedProductsRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Securitized Products Risk Member</link:label>
    <link:label id="lab_ck0000898745_SecuritizedProductsRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_SecuritizedProductsRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Securitized Products Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_SecuritizedProductsRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_SecuritizedProductsRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_SecuritizedProductsRiskMember" xlink:to="lab_ck0000898745_SecuritizedProductsRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019787Member_label_en-US" xlink:label="lab_ck0000898745_C000019787Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Real Estate Securities Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000019787Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019787Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Real Estate Securities, Class R-3, C000019787, PRERX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019787Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019787Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019787Member" xlink:to="lab_ck0000898745_C000019787Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019463Member_label_en-US" xlink:label="lab_ck0000898745_C000019463Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">LargeCap Value Fund III, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000019463Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019463Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">LargeCap Value III Fund, Institutional Class, C000019463, PLVIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019463Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019463Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019463Member" xlink:to="lab_ck0000898745_C000019463Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_FinisterreEmergingMarketsTotalReturnBondBlendedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_FinisterreEmergingMarketsTotalReturnBondBlendedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finisterre Emerging Markets Total Return Bond Blended Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_FinisterreEmergingMarketsTotalReturnBondBlendedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_FinisterreEmergingMarketsTotalReturnBondBlendedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Finisterre Emerging Markets Total Return Bond Blended Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_FinisterreEmergingMarketsTotalReturnBondBlendedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_FinisterreEmergingMarketsTotalReturnBondBlendedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_FinisterreEmergingMarketsTotalReturnBondBlendedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:to="lab_ck0000898745_FinisterreEmergingMarketsTotalReturnBondBlendedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000199318Member_label_en-US" xlink:label="lab_ck0000898745_C000199318Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2015 Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000199318Member_documentation_en-US" xlink:label="lab_ck0000898745_C000199318Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2015 Fund, Class J, C000199318</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000199318Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000199318Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000199318Member" xlink:to="lab_ck0000898745_C000199318Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000014238Member_label_en-US" xlink:label="lab_ck0000898745_S000014238Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal Capital Appreciation Fund</link:label>
    <link:label id="lab_ck0000898745_S000014238Member_documentation_en-US" xlink:label="lab_ck0000898745_S000014238Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal Capital Appreciation Fund, S000014238</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000014238Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000014238Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000014238Member" xlink:to="lab_ck0000898745_S000014238Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000199320Member_label_en-US" xlink:label="lab_ck0000898745_C000199320Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2025 Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000199320Member_documentation_en-US" xlink:label="lab_ck0000898745_C000199320Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2025 Fund, Class J, C000199320</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000199320Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000199320Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000199320Member" xlink:to="lab_ck0000898745_C000199320Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000006952Member_label_en-US" xlink:label="lab_ck0000898745_S000006952Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Core Plus Bond Fund</link:label>
    <link:label id="lab_ck0000898745_S000006952Member_documentation_en-US" xlink:label="lab_ck0000898745_S000006952Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Core Plus Bond Fund , S000006952</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000006952Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000006952Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000006952Member" xlink:to="lab_ck0000898745_S000006952Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019173Member_label_en-US" xlink:label="lab_ck0000898745_C000019173Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">LargeCap S&amp;P 500 Index Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000019173Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019173Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">LargeCap S&amp;P 500 Index Fund, Class J, C000019173, PSPJX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019173Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019173Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019173Member" xlink:to="lab_ck0000898745_C000019173Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038755Member_label_en-US" xlink:label="lab_ck0000898745_C000038755Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Core Fixed Income Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000038755Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038755Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Core Fixed Income Fund, Institutional Class, C000038755, PIOIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038755Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038755Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038755Member" xlink:to="lab_ck0000898745_C000038755Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000007175Member_label_en-US" xlink:label="lab_ck0000898745_S000007175Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SmallCap Growth Fund I</link:label>
    <link:label id="lab_ck0000898745_S000007175Member_documentation_en-US" xlink:label="lab_ck0000898745_S000007175Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SmallCap Growth Fund I, S000007175</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000007175Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000007175Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000007175Member" xlink:to="lab_ck0000898745_S000007175Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000175481Member_label_en-US" xlink:label="lab_ck0000898745_C000175481Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Global Emerging Markets Fund, Class R-6</link:label>
    <link:label id="lab_ck0000898745_C000175481Member_documentation_en-US" xlink:label="lab_ck0000898745_C000175481Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Global Emerging Markets Fund, Class R-6, C000175481</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000175481Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000175481Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000175481Member" xlink:to="lab_ck0000898745_C000175481Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019792Member_label_en-US" xlink:label="lab_ck0000898745_C000019792Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Real Estate Securities Fund, Class A</link:label>
    <link:label id="lab_ck0000898745_C000019792Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019792Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Real Estate Securities, Class A, C000019792, PRRAX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019792Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019792Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019792Member" xlink:to="lab_ck0000898745_C000019792Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000159885Member_label_en-US" xlink:label="lab_ck0000898745_C000159885Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2055 Fund, R-6</link:label>
    <link:label id="lab_ck0000898745_C000159885Member_documentation_en-US" xlink:label="lab_ck0000898745_C000159885Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2055 Fund, C000159885, R-6</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000159885Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000159885Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000159885Member" xlink:to="lab_ck0000898745_C000159885Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_ForeignCurrencyRiskMember_label_en-US" xlink:label="lab_ck0000898745_ForeignCurrencyRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Foreign Currency Risk Member</link:label>
    <link:label id="lab_ck0000898745_ForeignCurrencyRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_ForeignCurrencyRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Foreign Currency Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_ForeignCurrencyRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_ForeignCurrencyRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_ForeignCurrencyRiskMember" xlink:to="lab_ck0000898745_ForeignCurrencyRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000014242Member_label_en-US" xlink:label="lab_ck0000898745_S000014242Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Core Fixed Income Fund</link:label>
    <link:label id="lab_ck0000898745_S000014242Member_documentation_en-US" xlink:label="lab_ck0000898745_S000014242Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Core Fixed Income Fund, S000014242</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000014242Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000014242Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000014242Member" xlink:to="lab_ck0000898745_S000014242Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_FTSEEPRANAREITDevelopedMarketsIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_FTSEEPRANAREITDevelopedMarketsIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">FTSE EPRA NAREIT Developed Net Tax Index (reflects withholding taxes on foreign dividends, but no deduction for fees, expenses, or other taxes)</link:label>
    <link:label id="lab_ck0000898745_FTSEEPRANAREITDevelopedMarketsIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_FTSEEPRANAREITDevelopedMarketsIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">FTSE EPRA NAREIT Developed Net Tax Index (reflects withholding taxes on foreign dividends, but no deduction for fees, expenses, or other taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_FTSEEPRANAREITDevelopedMarketsIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_FTSEEPRANAREITDevelopedMarketsIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_FTSEEPRANAREITDevelopedMarketsIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember" xlink:to="lab_ck0000898745_FTSEEPRANAREITDevelopedMarketsIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000039355Member_label_en-US" xlink:label="lab_ck0000898745_C000039355Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Strategic Growth Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000039355Member_documentation_en-US" xlink:label="lab_ck0000898745_C000039355Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Strategic Growth Fund, Class R-3, C000039355, PSGPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000039355Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000039355Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000039355Member" xlink:to="lab_ck0000898745_C000039355Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_USGovernmentSponsoredSecuritiesRiskMember_label_en-US" xlink:label="lab_ck0000898745_USGovernmentSponsoredSecuritiesRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">U.S. Government-Sponsored Securities Risk Member</link:label>
    <link:label id="lab_ck0000898745_USGovernmentSponsoredSecuritiesRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_USGovernmentSponsoredSecuritiesRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">U.S. Government-Sponsored Securities Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_USGovernmentSponsoredSecuritiesRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_USGovernmentSponsoredSecuritiesRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_USGovernmentSponsoredSecuritiesRiskMember" xlink:to="lab_ck0000898745_USGovernmentSponsoredSecuritiesRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000007122Member_label_en-US" xlink:label="lab_ck0000898745_S000007122Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">LargeCap Value Fund III</link:label>
    <link:label id="lab_ck0000898745_S000007122Member_documentation_en-US" xlink:label="lab_ck0000898745_S000007122Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">LargeCap Value Fund III, S000007122</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000007122Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000007122Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000007122Member" xlink:to="lab_ck0000898745_S000007122Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019717Member_label_en-US" xlink:label="lab_ck0000898745_C000019717Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SmallCap S&amp;P 600 Index Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000019717Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019717Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SmallCap S&amp;P 600 Index Fund, Class R-5, C000019717, PSSPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019717Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019717Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019717Member" xlink:to="lab_ck0000898745_C000019717Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019765Member_label_en-US" xlink:label="lab_ck0000898745_C000019765Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2040 Fund, Class A</link:label>
    <link:label id="lab_ck0000898745_C000019765Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019765Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2040 Fund, Class A, C000019765, PTDAX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019765Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019765Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019765Member" xlink:to="lab_ck0000898745_C000019765Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_ForeignSecuritiesRiskMember_label_en-US" xlink:label="lab_ck0000898745_ForeignSecuritiesRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Foreign Securities Risk Member</link:label>
    <link:label id="lab_ck0000898745_ForeignSecuritiesRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_ForeignSecuritiesRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Foreign Securities Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_ForeignSecuritiesRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_ForeignSecuritiesRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_ForeignSecuritiesRiskMember" xlink:to="lab_ck0000898745_ForeignSecuritiesRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000159892Member_label_en-US" xlink:label="lab_ck0000898745_C000159892Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2040 Fund, R-6</link:label>
    <link:label id="lab_ck0000898745_C000159892Member_documentation_en-US" xlink:label="lab_ck0000898745_C000159892Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2040 Fund, C000159892, R-6</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000159892Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000159892Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000159892Member" xlink:to="lab_ck0000898745_C000159892Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000071807Member_label_en-US" xlink:label="lab_ck0000898745_C000071807Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Diversified Income Fund, Class A</link:label>
    <link:label id="lab_ck0000898745_C000071807Member_documentation_en-US" xlink:label="lab_ck0000898745_C000071807Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Diversified Income Fund, Class A, C000071807, PGBAX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000071807Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000071807Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000071807Member" xlink:to="lab_ck0000898745_C000071807Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_SPTargetDate2025IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_SPTargetDate2025IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">S&amp;P Target Date 2025 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_SPTargetDate2025IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_SPTargetDate2025IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">S&amp;P Target Date 2025 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_SPTargetDate2025IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_SPTargetDate2025IndexreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_SPTargetDate2025IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0000898745_SPTargetDate2025IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_DerivativesRiskCurrencyContractsRiskMember_label_en-US" xlink:label="lab_ck0000898745_DerivativesRiskCurrencyContractsRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Derivatives Risk, Currency Contracts Risk Member</link:label>
    <link:label id="lab_ck0000898745_DerivativesRiskCurrencyContractsRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_DerivativesRiskCurrencyContractsRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Derivatives Risk, Currency Contracts Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_DerivativesRiskCurrencyContractsRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_DerivativesRiskCurrencyContractsRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_DerivativesRiskCurrencyContractsRiskMember" xlink:to="lab_ck0000898745_DerivativesRiskCurrencyContractsRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000063431Member_label_en-US" xlink:label="lab_ck0000898745_C000063431Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2025 Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000063431Member_documentation_en-US" xlink:label="lab_ck0000898745_C000063431Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2025 Fund, Class R-3, C000063431, LTVPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000063431Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000063431Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000063431Member" xlink:to="lab_ck0000898745_C000063431Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019784Member_label_en-US" xlink:label="lab_ck0000898745_C000019784Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Strategic Income Fund, Class A</link:label>
    <link:label id="lab_ck0000898745_C000019784Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019784Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Strategic Income Fund, Class A, C000019784, PALTX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019784Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019784Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019784Member" xlink:to="lab_ck0000898745_C000019784Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038750Member_label_en-US" xlink:label="lab_ck0000898745_C000038750Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">High Yield Fund, Class C</link:label>
    <link:label id="lab_ck0000898745_C000038750Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038750Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">High Yield Fund, Class C, C000038750, CCHIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038750Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038750Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038750Member" xlink:to="lab_ck0000898745_C000038750Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000022104Member_label_en-US" xlink:label="lab_ck0000898745_S000022104Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2025 Fund</link:label>
    <link:label id="lab_ck0000898745_S000022104Member_documentation_en-US" xlink:label="lab_ck0000898745_S000022104Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2025 Fund, S000022104</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000022104Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000022104Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000022104Member" xlink:to="lab_ck0000898745_S000022104Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000175486Member_label_en-US" xlink:label="lab_ck0000898745_C000175486Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Real Estate Securities Fund, Class R-6</link:label>
    <link:label id="lab_ck0000898745_C000175486Member_documentation_en-US" xlink:label="lab_ck0000898745_C000175486Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Real Estate Securities Fund, Class R-6, C000175486</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000175486Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000175486Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000175486Member" xlink:to="lab_ck0000898745_C000175486Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000014234Member_label_en-US" xlink:label="lab_ck0000898745_S000014234Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Strategic Asset Management Conservative Growth Portfolio</link:label>
    <link:label id="lab_ck0000898745_S000014234Member_documentation_en-US" xlink:label="lab_ck0000898745_S000014234Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Strategic Asset Management Conservative Growth Portfolio, S000014234</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000014234Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000014234Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000014234Member" xlink:to="lab_ck0000898745_S000014234Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000006997Member_label_en-US" xlink:label="lab_ck0000898745_S000006997Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inflation Protection Fund</link:label>
    <link:label id="lab_ck0000898745_S000006997Member_documentation_en-US" xlink:label="lab_ck0000898745_S000006997Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Inflation Protection Fund, S000006997</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000006997Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000006997Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000006997Member" xlink:to="lab_ck0000898745_S000006997Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_SAMConservativeGrowthBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_SAMConservativeGrowthBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Conservative Growth Blended Index (except as noted for MSCI ACWI Index NTR, reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_SAMConservativeGrowthBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_SAMConservativeGrowthBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Conservative Growth Blended Index (except as noted for MSCI ACWI Index NTR, reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_SAMConservativeGrowthBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_SAMConservativeGrowthBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_SAMConservativeGrowthBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:to="lab_ck0000898745_SAMConservativeGrowthBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000014241Member_label_en-US" xlink:label="lab_ck0000898745_S000014241Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">High Yield Fund</link:label>
    <link:label id="lab_ck0000898745_S000014241Member_documentation_en-US" xlink:label="lab_ck0000898745_S000014241Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">High Yield Fund, S000014241</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000014241Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000014241Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000014241Member" xlink:to="lab_ck0000898745_S000014241Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_SPTargetDate2055IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_SPTargetDate2055IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">S&amp;P Target Date 2055 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_SPTargetDate2055IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_SPTargetDate2055IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">S&amp;P Target Date 2055 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_SPTargetDate2055IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_SPTargetDate2055IndexreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_SPTargetDate2055IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0000898745_SPTargetDate2055IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_DistressedInvestmentsRiskMember_label_en-US" xlink:label="lab_ck0000898745_DistressedInvestmentsRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Distressed Investments Risk Member</link:label>
    <link:label id="lab_ck0000898745_DistressedInvestmentsRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_DistressedInvestmentsRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Distressed Investments Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_DistressedInvestmentsRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_DistressedInvestmentsRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_DistressedInvestmentsRiskMember" xlink:to="lab_ck0000898745_DistressedInvestmentsRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000145308Member_label_en-US" xlink:label="lab_ck0000898745_C000145308Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2060 Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000145308Member_documentation_en-US" xlink:label="lab_ck0000898745_C000145308Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2060 Fund, Institutional Class, C000145308, PLTHX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000145308Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000145308Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000145308Member" xlink:to="lab_ck0000898745_C000145308Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_SandPMidcap400IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_SandPMidcap400IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">S&amp;P Midcap 400 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_SandPMidcap400IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_SandPMidcap400IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">S&amp;P Midcap 400 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_SandPMidcap400IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_SandPMidcap400IndexreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_SandPMidcap400IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0000898745_SandPMidcap400IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000014235Member_label_en-US" xlink:label="lab_ck0000898745_S000014235Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Strategic Asset Management Flexible Income Portfolio</link:label>
    <link:label id="lab_ck0000898745_S000014235Member_documentation_en-US" xlink:label="lab_ck0000898745_S000014235Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Strategic Asset Management Flexible Income Portfolio, S000014235</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000014235Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000014235Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000014235Member" xlink:to="lab_ck0000898745_S000014235Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000022103Member_label_en-US" xlink:label="lab_ck0000898745_S000022103Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2015 Fund</link:label>
    <link:label id="lab_ck0000898745_S000022103Member_documentation_en-US" xlink:label="lab_ck0000898745_S000022103Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2015 Fund, S000022103</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000022103Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000022103Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000022103Member" xlink:to="lab_ck0000898745_S000022103Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_SAMStrategicGrowthBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_SAMStrategicGrowthBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Strategic Growth Blended Index (except as noted for MSCI ACWI Index NTR, reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_SAMStrategicGrowthBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_SAMStrategicGrowthBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Strategic Growth Blended Index (except as noted for MSCI ACWI Index NTR, reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_SAMStrategicGrowthBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_SAMStrategicGrowthBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_SAMStrategicGrowthBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:to="lab_ck0000898745_SAMStrategicGrowthBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000159884Member_label_en-US" xlink:label="lab_ck0000898745_C000159884Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid Income Fund, R-6</link:label>
    <link:label id="lab_ck0000898745_C000159884Member_documentation_en-US" xlink:label="lab_ck0000898745_C000159884Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid Income Fund, R-6, C000159884, PLTYX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000159884Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000159884Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000159884Member" xlink:to="lab_ck0000898745_C000159884Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000271982Member_label_en-US" xlink:label="lab_ck0000898745_C000271982Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">International Bond Fund Class R-6</link:label>
    <link:label id="lab_ck0000898745_C000271982Member_documentation_en-US" xlink:label="lab_ck0000898745_C000271982Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">International Bond Fund Class R-6, C000271982</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000271982Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000271982Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000271982Member" xlink:to="lab_ck0000898745_C000271982Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019773Member_label_en-US" xlink:label="lab_ck0000898745_C000019773Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2050 Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000019773Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019773Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2050 Fund, Institutional Class, C000019773, PPLIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019773Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019773Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019773Member" xlink:to="lab_ck0000898745_C000019773Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000175487Member_label_en-US" xlink:label="lab_ck0000898745_C000175487Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SmallCap Fund, Class R-6</link:label>
    <link:label id="lab_ck0000898745_C000175487Member_documentation_en-US" xlink:label="lab_ck0000898745_C000175487Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SmallCap Fund, Class R-6, C000175487</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000175487Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000175487Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000175487Member" xlink:to="lab_ck0000898745_C000175487Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019460Member_label_en-US" xlink:label="lab_ck0000898745_C000019460Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">LargeCap Value Fund III, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000019460Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019460Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">LargeCap Value III Fund, Class R-3, C000019460, PPSFX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019460Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019460Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019460Member" xlink:to="lab_ck0000898745_C000019460Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000007214Member_label_en-US" xlink:label="lab_ck0000898745_S000007214Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SmallCap Fund</link:label>
    <link:label id="lab_ck0000898745_S000007214Member_documentation_en-US" xlink:label="lab_ck0000898745_S000007214Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SmallCap Fund, S000007214</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000007214Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000007214Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000007214Member" xlink:to="lab_ck0000898745_S000007214Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000039349Member_label_en-US" xlink:label="lab_ck0000898745_C000039349Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Flexible Income Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000039349Member_documentation_en-US" xlink:label="lab_ck0000898745_C000039349Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Flexible Income Fund, Class R-3, C000039349, PFIPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000039349Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000039349Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000039349Member" xlink:to="lab_ck0000898745_C000039349Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000039343Member_label_en-US" xlink:label="lab_ck0000898745_C000039343Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Conservative Growth Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000039343Member_documentation_en-US" xlink:label="lab_ck0000898745_C000039343Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Conservative Growth Fund, Class R-5, C000039343, PCWPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000039343Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000039343Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000039343Member" xlink:to="lab_ck0000898745_C000039343Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000145302Member_label_en-US" xlink:label="lab_ck0000898745_C000145302Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid Income Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000145302Member_documentation_en-US" xlink:label="lab_ck0000898745_C000145302Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid Income Fund, Institutional Class, C000145302, PHTFX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000145302Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000145302Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000145302Member" xlink:to="lab_ck0000898745_C000145302Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000145314Member_label_en-US" xlink:label="lab_ck0000898745_C000145314Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2020 Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000145314Member_documentation_en-US" xlink:label="lab_ck0000898745_C000145314Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2020 Fund, Institutional Class, C000145314, PHTTX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000145314Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000145314Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000145314Member" xlink:to="lab_ck0000898745_C000145314Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019328Member_label_en-US" xlink:label="lab_ck0000898745_C000019328Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">LargeCap Growth Fund I, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000019328Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019328Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">LargeCap Growth I Fund, Class R-3, C000019328, PPUMX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019328Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019328Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019328Member" xlink:to="lab_ck0000898745_C000019328Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019055Member_label_en-US" xlink:label="lab_ck0000898745_C000019055Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Diversified International Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000019055Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019055Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Diversified International Fund, Class R-5, C000019055, PINPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019055Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019055Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019055Member" xlink:to="lab_ck0000898745_C000019055Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_MSCIACWIExUSAIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_MSCIACWIExUSAIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MSCI ACWI Ex USA Index NTR (reflects withholding taxes on foreign dividends, but no deduction for fees, expenses, or other taxes)</link:label>
    <link:label id="lab_ck0000898745_MSCIACWIExUSAIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_MSCIACWIExUSAIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MSCI ACWI Ex USA Index NTR (reflects withholding taxes on foreign dividends, but no deduction for fees, expenses, or other taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_MSCIACWIExUSAIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_MSCIACWIExUSAIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_MSCIACWIExUSAIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember" xlink:to="lab_ck0000898745_MSCIACWIExUSAIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019716Member_label_en-US" xlink:label="lab_ck0000898745_C000019716Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SmallCap S&amp;P 600 Index Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000019716Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019716Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SmallCap S&amp;P 600 Index Fund, Class R-3, C000019716, PSSMX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019716Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019716Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019716Member" xlink:to="lab_ck0000898745_C000019716Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_MunicipalObligationsRiskMember_label_en-US" xlink:label="lab_ck0000898745_MunicipalObligationsRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Municipal Obligations Risk Member</link:label>
    <link:label id="lab_ck0000898745_MunicipalObligationsRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_MunicipalObligationsRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Municipal Obligations Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_MunicipalObligationsRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_MunicipalObligationsRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_MunicipalObligationsRiskMember" xlink:to="lab_ck0000898745_MunicipalObligationsRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000063423Member_label_en-US" xlink:label="lab_ck0000898745_C000063423Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2015 Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000063423Member_documentation_en-US" xlink:label="lab_ck0000898745_C000063423Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2015 Fund, Institutional Class, C000063423, LTINX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000063423Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000063423Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000063423Member" xlink:to="lab_ck0000898745_C000063423Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000159891Member_label_en-US" xlink:label="lab_ck0000898745_C000159891Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2035 Fund, R-6</link:label>
    <link:label id="lab_ck0000898745_C000159891Member_documentation_en-US" xlink:label="lab_ck0000898745_C000159891Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2035 Fund, C000159891, R-6</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000159891Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000159891Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000159891Member" xlink:to="lab_ck0000898745_C000159891Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_DerivativesRiskFuturesAndSwapsRiskMember_label_en-US" xlink:label="lab_ck0000898745_DerivativesRiskFuturesAndSwapsRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Derivatives Risk, Futures And Swaps Risk Member</link:label>
    <link:label id="lab_ck0000898745_DerivativesRiskFuturesAndSwapsRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_DerivativesRiskFuturesAndSwapsRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Derivatives Risk, Futures And Swaps Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_DerivativesRiskFuturesAndSwapsRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_DerivativesRiskFuturesAndSwapsRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_DerivativesRiskFuturesAndSwapsRiskMember" xlink:to="lab_ck0000898745_DerivativesRiskFuturesAndSwapsRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019615Member_label_en-US" xlink:label="lab_ck0000898745_C000019615Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MidCap Value I Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000019615Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019615Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MidCap Value I Fund, Class R-5, C000019615, PABVX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019615Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019615Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019615Member" xlink:to="lab_ck0000898745_C000019615Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000022105Member_label_en-US" xlink:label="lab_ck0000898745_S000022105Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2035 Fund</link:label>
    <link:label id="lab_ck0000898745_S000022105Member_documentation_en-US" xlink:label="lab_ck0000898745_S000022105Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2035 Fund, S000022105</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000022105Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000022105Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000022105Member" xlink:to="lab_ck0000898745_S000022105Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000175485Member_label_en-US" xlink:label="lab_ck0000898745_C000175485Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SmallCap S&amp;P 600 Index Fund, Class R-6</link:label>
    <link:label id="lab_ck0000898745_C000175485Member_documentation_en-US" xlink:label="lab_ck0000898745_C000175485Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SmallCap S&amp;P 600 Index Fund, Class R-6, C000175485</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000175485Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000175485Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000175485Member" xlink:to="lab_ck0000898745_C000175485Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000159889Member_label_en-US" xlink:label="lab_ck0000898745_C000159889Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2025 Fund, R-6</link:label>
    <link:label id="lab_ck0000898745_C000159889Member_documentation_en-US" xlink:label="lab_ck0000898745_C000159889Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2025 Fund, R-6, C000159889, PLFTX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000159889Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000159889Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000159889Member" xlink:to="lab_ck0000898745_C000159889Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019329Member_label_en-US" xlink:label="lab_ck0000898745_C000019329Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">LargeCap Growth Fund I, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000019329Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019329Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">LargeCap Growth I Fund, Class R-5, C000019329, PPUPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019329Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019329Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019329Member" xlink:to="lab_ck0000898745_C000019329Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_BloombergUSAggregateIndex1reflectsNoDeductionForFeesExpensesOrTaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_BloombergUSAggregateIndex1reflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Bloomberg US Aggregate Index 1(reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_BloombergUSAggregateIndex1reflectsNoDeductionForFeesExpensesOrTaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_BloombergUSAggregateIndex1reflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Bloomberg US Aggregate Index 1(reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_BloombergUSAggregateIndex1reflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_BloombergUSAggregateIndex1reflectsNoDeductionForFeesExpensesOrTaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_BloombergUSAggregateIndex1reflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:to="lab_ck0000898745_BloombergUSAggregateIndex1reflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000090496Member_label_en-US" xlink:label="lab_ck0000898745_C000090496Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Short-Term Income Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000090496Member_documentation_en-US" xlink:label="lab_ck0000898745_C000090496Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Short-Term Income Fund, Class R-3 Shares, C000090496, PSIOX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000090496Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000090496Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000090496Member" xlink:to="lab_ck0000898745_C000090496Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019172Member_label_en-US" xlink:label="lab_ck0000898745_C000019172Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">LargeCap S&amp;P 500 Index Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000019172Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019172Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">LargeCap S&amp;P 500 Index Fund, Institutional Class, C000019172, PLFIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019172Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019172Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019172Member" xlink:to="lab_ck0000898745_C000019172Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038746Member_label_en-US" xlink:label="lab_ck0000898745_C000038746Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equity Income Fund, Class C</link:label>
    <link:label id="lab_ck0000898745_C000038746Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038746Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Equity Income Fund, Class C, C000038746, PEUCX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038746Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038746Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038746Member" xlink:to="lab_ck0000898745_C000038746Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038751Member_label_en-US" xlink:label="lab_ck0000898745_C000038751Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">High Yield Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000038751Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038751Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">High Yield Fund, Institutional Class, C000038751, PHYTX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038751Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038751Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038751Member" xlink:to="lab_ck0000898745_C000038751Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000018961Member_label_en-US" xlink:label="lab_ck0000898745_C000018961Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Core Plus Bond Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000018961Member_documentation_en-US" xlink:label="lab_ck0000898745_C000018961Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Core Plus Bond Fund, Institutional Class, C000018961, PMSIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000018961Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000018961Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000018961Member" xlink:to="lab_ck0000898745_C000018961Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000159894Member_label_en-US" xlink:label="lab_ck0000898745_C000159894Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2050 Fund, R-6</link:label>
    <link:label id="lab_ck0000898745_C000159894Member_documentation_en-US" xlink:label="lab_ck0000898745_C000159894Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2050 Fund, C000159894, R-6</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000159894Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000159894Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000159894Member" xlink:to="lab_ck0000898745_C000159894Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019783Member_label_en-US" xlink:label="lab_ck0000898745_C000019783Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Strategic Income Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000019783Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019783Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Strategic Income Fund, Class J, C000019783, PLSJX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019783Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019783Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019783Member" xlink:to="lab_ck0000898745_C000019783Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_JPMEMBIGlobalDiversifiedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_JPMEMBIGlobalDiversifiedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">JPM EMBI Global Diversified Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_JPMEMBIGlobalDiversifiedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_JPMEMBIGlobalDiversifiedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">JPM EMBI Global Diversified Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_JPMEMBIGlobalDiversifiedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_JPMEMBIGlobalDiversifiedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_JPMEMBIGlobalDiversifiedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:to="lab_ck0000898745_JPMEMBIGlobalDiversifiedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_USGovernmentSecuritiesRiskMember_label_en-US" xlink:label="lab_ck0000898745_USGovernmentSecuritiesRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">U.S. Government Securities Risk Member</link:label>
    <link:label id="lab_ck0000898745_USGovernmentSecuritiesRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_USGovernmentSecuritiesRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">U.S. Government Securities Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_USGovernmentSecuritiesRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_USGovernmentSecuritiesRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_USGovernmentSecuritiesRiskMember" xlink:to="lab_ck0000898745_USGovernmentSecuritiesRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000175482Member_label_en-US" xlink:label="lab_ck0000898745_C000175482Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MidCap Fund, Class R-6</link:label>
    <link:label id="lab_ck0000898745_C000175482Member_documentation_en-US" xlink:label="lab_ck0000898745_C000175482Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MidCap Fund, Class R-6, C000175482</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000175482Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000175482Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000175482Member" xlink:to="lab_ck0000898745_C000175482Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000039344Member_label_en-US" xlink:label="lab_ck0000898745_C000039344Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Conservative Growth Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000039344Member_documentation_en-US" xlink:label="lab_ck0000898745_C000039344Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Conservative Growth Fund, Class J, C000039344, PCGJX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000039344Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000039344Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000039344Member" xlink:to="lab_ck0000898745_C000039344Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_PreferredSecuritiesRiskMember_label_en-US" xlink:label="lab_ck0000898745_PreferredSecuritiesRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Preferred Securities Risk Member</link:label>
    <link:label id="lab_ck0000898745_PreferredSecuritiesRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_PreferredSecuritiesRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Preferred Securities Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_PreferredSecuritiesRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_PreferredSecuritiesRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_PreferredSecuritiesRiskMember" xlink:to="lab_ck0000898745_PreferredSecuritiesRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019057Member_label_en-US" xlink:label="lab_ck0000898745_C000019057Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Diversified International Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000019057Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019057Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Diversified International Fund, Institutional Class, C000019057, PIIIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019057Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019057Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019057Member" xlink:to="lab_ck0000898745_C000019057Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000167005Member_label_en-US" xlink:label="lab_ck0000898745_C000167005Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Global Real Estate Securities Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000167005Member_documentation_en-US" xlink:label="lab_ck0000898745_C000167005Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Global Real Estate Securities Fund, Class R-3, C000167005</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000167005Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000167005Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000167005Member" xlink:to="lab_ck0000898745_C000167005Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000090493Member_label_en-US" xlink:label="lab_ck0000898745_C000090493Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Short-Term Income Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000090493Member_documentation_en-US" xlink:label="lab_ck0000898745_C000090493Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Short-Term Income Fund, Class J Shares, C000090493, PSJIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000090493Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000090493Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000090493Member" xlink:to="lab_ck0000898745_C000090493Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_BloombergCaliforniaMunicipalIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_BloombergCaliforniaMunicipalIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Bloomberg California Municipal Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_BloombergCaliforniaMunicipalIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_BloombergCaliforniaMunicipalIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Bloomberg California Municipal Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_BloombergCaliforniaMunicipalIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_BloombergCaliforniaMunicipalIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_BloombergCaliforniaMunicipalIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:to="lab_ck0000898745_BloombergCaliforniaMunicipalIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000159886Member_label_en-US" xlink:label="lab_ck0000898745_C000159886Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2060 Fund, R-6</link:label>
    <link:label id="lab_ck0000898745_C000159886Member_documentation_en-US" xlink:label="lab_ck0000898745_C000159886Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2060 Fund, C000159886, R-6</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000159886Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000159886Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000159886Member" xlink:to="lab_ck0000898745_C000159886Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000014233Member_label_en-US" xlink:label="lab_ck0000898745_S000014233Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Strategic Asset Management Conservative Balanced Portfolio</link:label>
    <link:label id="lab_ck0000898745_S000014233Member_documentation_en-US" xlink:label="lab_ck0000898745_S000014233Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Strategic Asset Management Conservative Balanced Portfolio, S000014233</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000014233Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000014233Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000014233Member" xlink:to="lab_ck0000898745_S000014233Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000063426Member_label_en-US" xlink:label="lab_ck0000898745_C000063426Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2015 Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000063426Member_documentation_en-US" xlink:label="lab_ck0000898745_C000063426Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2015 Fund, Class R-5, C000063426, LTPFX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000063426Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000063426Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000063426Member" xlink:to="lab_ck0000898745_C000063426Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019343Member_label_en-US" xlink:label="lab_ck0000898745_C000019343Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MidCap S&amp;P 400 Index Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000019343Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019343Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MidCap S&amp;P 400 Index Fund, Institutional Class, C000019343, MPSIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019343Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019343Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019343Member" xlink:to="lab_ck0000898745_C000019343Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000123724Member_label_en-US" xlink:label="lab_ck0000898745_C000123724Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2060 Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000123724Member_documentation_en-US" xlink:label="lab_ck0000898745_C000123724Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2060 Fund, Class R-3, C000123724</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000123724Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000123724Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000123724Member" xlink:to="lab_ck0000898745_C000123724Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000159893Member_label_en-US" xlink:label="lab_ck0000898745_C000159893Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2045 Fund, R-6</link:label>
    <link:label id="lab_ck0000898745_C000159893Member_documentation_en-US" xlink:label="lab_ck0000898745_C000159893Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2045 Fund, C000159893 R-6</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000159893Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000159893Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000159893Member" xlink:to="lab_ck0000898745_C000159893Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038747Member_label_en-US" xlink:label="lab_ck0000898745_C000038747Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equity Income Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000038747Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038747Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Equity Income Fund, Institutional Class, C000038747, PEIIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038747Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038747Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038747Member" xlink:to="lab_ck0000898745_C000038747Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000123721Member_label_en-US" xlink:label="lab_ck0000898745_C000123721Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2060 Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000123721Member_documentation_en-US" xlink:label="lab_ck0000898745_C000123721Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2060 Fund, Class J, C000123721</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000123721Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000123721Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000123721Member" xlink:to="lab_ck0000898745_C000123721Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_DerivativesRiskCreditDefaultSwapsRiskMember_label_en-US" xlink:label="lab_ck0000898745_DerivativesRiskCreditDefaultSwapsRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Derivatives Risk, Credit Default Swaps Risk Member</link:label>
    <link:label id="lab_ck0000898745_DerivativesRiskCreditDefaultSwapsRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_DerivativesRiskCreditDefaultSwapsRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Derivatives Risk, Credit Default Swaps Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_DerivativesRiskCreditDefaultSwapsRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_DerivativesRiskCreditDefaultSwapsRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_DerivativesRiskCreditDefaultSwapsRiskMember" xlink:to="lab_ck0000898745_DerivativesRiskCreditDefaultSwapsRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000145311Member_label_en-US" xlink:label="lab_ck0000898745_C000145311Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2015 Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000145311Member_documentation_en-US" xlink:label="lab_ck0000898745_C000145311Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2015 Fund, Institutional Class, C000145311, PHTMX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000145311Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000145311Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000145311Member" xlink:to="lab_ck0000898745_C000145311Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000018962Member_label_en-US" xlink:label="lab_ck0000898745_C000018962Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Core Plus Bond Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000018962Member_documentation_en-US" xlink:label="lab_ck0000898745_C000018962Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Core Plus Bond Fund, Class J, C000018962, PBMJX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000018962Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000018962Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000018962Member" xlink:to="lab_ck0000898745_C000018962Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000018959Member_label_en-US" xlink:label="lab_ck0000898745_C000018959Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Core Plus Bond Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000018959Member_documentation_en-US" xlink:label="lab_ck0000898745_C000018959Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Core Plus Bond Fund, Class R-5, C000018959, PBMPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000018959Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000018959Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000018959Member" xlink:to="lab_ck0000898745_C000018959Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000175483Member_label_en-US" xlink:label="lab_ck0000898745_C000175483Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MidCap S&amp;P 400 Index Fund, Class R-6</link:label>
    <link:label id="lab_ck0000898745_C000175483Member_documentation_en-US" xlink:label="lab_ck0000898745_C000175483Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MidCap S&amp;P 400 Index Fund, Class R-6, C000175483</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000175483Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000175483Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000175483Member" xlink:to="lab_ck0000898745_C000175483Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000022107Member_label_en-US" xlink:label="lab_ck0000898745_S000022107Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2055 Fund</link:label>
    <link:label id="lab_ck0000898745_S000022107Member_documentation_en-US" xlink:label="lab_ck0000898745_S000022107Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2055 Fund, S000022107</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000022107Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000022107Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000022107Member" xlink:to="lab_ck0000898745_S000022107Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000039352Member_label_en-US" xlink:label="lab_ck0000898745_C000039352Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Flexible Income Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000039352Member_documentation_en-US" xlink:label="lab_ck0000898745_C000039352Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Flexible Income Fund, Class R-5, C000039352, PFIFX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000039352Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000039352Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000039352Member" xlink:to="lab_ck0000898745_C000039352Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_Russell3000IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_Russell3000IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Russell 3000 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_Russell3000IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_Russell3000IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Russell 3000 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_Russell3000IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_Russell3000IndexreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_Russell3000IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0000898745_Russell3000IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_SAMConservativeBalancedBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_SAMConservativeBalancedBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Conservative Balanced Blended Index (except as noted for MSCI ACWI Index NTR, reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_SAMConservativeBalancedBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_SAMConservativeBalancedBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Conservative Balanced Blended Index (except as noted for MSCI ACWI Index NTR, reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_SAMConservativeBalancedBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_SAMConservativeBalancedBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_SAMConservativeBalancedBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:to="lab_ck0000898745_SAMConservativeBalancedBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019174Member_label_en-US" xlink:label="lab_ck0000898745_C000019174Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">LargeCap S&amp;P 500 Index Fund, Class A</link:label>
    <link:label id="lab_ck0000898745_C000019174Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019174Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">LargeCap S&amp;P 500 Index Fund, Class A, C000019174, PLSAX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019174Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019174Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019174Member" xlink:to="lab_ck0000898745_C000019174Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000159887Member_label_en-US" xlink:label="lab_ck0000898745_C000159887Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2015 Fund, R-6 [Member]</link:label>
    <link:label id="lab_ck0000898745_C000159887Member_documentation_en-US" xlink:label="lab_ck0000898745_C000159887Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2015 Fund, R-6, C000159887, PLRRX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000159887Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000159887Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000159887Member" xlink:to="lab_ck0000898745_C000159887Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019780Member_label_en-US" xlink:label="lab_ck0000898745_C000019780Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Strategic Income Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000019780Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019780Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Strategic Income Fund, Class R-5, C000019780, PLSPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019780Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019780Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019780Member" xlink:to="lab_ck0000898745_C000019780Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019775Member_label_en-US" xlink:label="lab_ck0000898745_C000019775Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2050 Fund, Class A</link:label>
    <link:label id="lab_ck0000898745_C000019775Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019775Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2050 Fund, Class A, C000019775, PPEAX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019775Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019775Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019775Member" xlink:to="lab_ck0000898745_C000019775Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000080382Member_label_en-US" xlink:label="lab_ck0000898745_C000080382Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Core Fixed Income Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000080382Member_documentation_en-US" xlink:label="lab_ck0000898745_C000080382Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Core Fixed Income Fund, Class J, C000080382, PIOJX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000080382Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000080382Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000080382Member" xlink:to="lab_ck0000898745_C000080382Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000063424Member_label_en-US" xlink:label="lab_ck0000898745_C000063424Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2015 Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000063424Member_documentation_en-US" xlink:label="lab_ck0000898745_C000063424Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2015 Fund, Class R-3, C000063424, LTAPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000063424Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000063424Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000063424Member" xlink:to="lab_ck0000898745_C000063424Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019059Member_label_en-US" xlink:label="lab_ck0000898745_C000019059Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Diversified International Fund, Class A</link:label>
    <link:label id="lab_ck0000898745_C000019059Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019059Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Diversified International Fund, Class A, C000019059, PRWLX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019059Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019059Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019059Member" xlink:to="lab_ck0000898745_C000019059Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000145305Member_label_en-US" xlink:label="lab_ck0000898745_C000145305Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2055 Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000145305Member_documentation_en-US" xlink:label="lab_ck0000898745_C000145305Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2055 Fund, Institutional Class, C000145305, PLTNX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000145305Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000145305Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000145305Member" xlink:to="lab_ck0000898745_C000145305Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_EmergingMarketsRiskChinaInvestmentRiskMember_label_en-US" xlink:label="lab_ck0000898745_EmergingMarketsRiskChinaInvestmentRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Emerging Markets Risk, China Investment Risk Member</link:label>
    <link:label id="lab_ck0000898745_EmergingMarketsRiskChinaInvestmentRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_EmergingMarketsRiskChinaInvestmentRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Emerging Markets Risk, China Investment Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_EmergingMarketsRiskChinaInvestmentRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_EmergingMarketsRiskChinaInvestmentRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_EmergingMarketsRiskChinaInvestmentRiskMember" xlink:to="lab_ck0000898745_EmergingMarketsRiskChinaInvestmentRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_Russell1000ValueIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_Russell1000ValueIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Russell 1000 Value Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_Russell1000ValueIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_Russell1000ValueIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Russell 1000 Value Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_Russell1000ValueIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_Russell1000ValueIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_Russell1000ValueIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:to="lab_ck0000898745_Russell1000ValueIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_SPTargetDate2020IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_SPTargetDate2020IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">S&amp;P Target Date 2020 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_SPTargetDate2020IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_SPTargetDate2020IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">S&amp;P Target Date 2020 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_SPTargetDate2020IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_SPTargetDate2020IndexreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_SPTargetDate2020IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0000898745_SPTargetDate2020IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019614Member_label_en-US" xlink:label="lab_ck0000898745_C000019614Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MidCap Value I Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000019614Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019614Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MidCap Value I Fund, Class R-3, C000019614, PMPRX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019614Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019614Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019614Member" xlink:to="lab_ck0000898745_C000019614Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000018963Member_label_en-US" xlink:label="lab_ck0000898745_C000018963Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Core Plus Bond Fund, Class A</link:label>
    <link:label id="lab_ck0000898745_C000018963Member_documentation_en-US" xlink:label="lab_ck0000898745_C000018963Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Core Plus Bond Fund, Class A, C000018963, PRBDX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000018963Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000018963Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000018963Member" xlink:to="lab_ck0000898745_C000018963Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_SAMBalancedBlendedIndexexceptasnotedforMSCIEAFEIndexNTRreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_SAMBalancedBlendedIndexexceptasnotedforMSCIEAFEIndexNTRreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Balanced Blended Index (except as noted for MSCI EAFE Index NTR, reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_SAMBalancedBlendedIndexexceptasnotedforMSCIEAFEIndexNTRreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_SAMBalancedBlendedIndexexceptasnotedforMSCIEAFEIndexNTRreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Balanced Blended Index (except as noted for MSCI EAFE Index NTR, reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_SAMBalancedBlendedIndexexceptasnotedforMSCIEAFEIndexNTRreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_SAMBalancedBlendedIndexexceptasnotedforMSCIEAFEIndexNTRreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_SAMBalancedBlendedIndexexceptasnotedforMSCIEAFEIndexNTRreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0000898745_SAMBalancedBlendedIndexexceptasnotedforMSCIEAFEIndexNTRreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_FTSENAREITAllEquityREITIndexreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_FTSENAREITAllEquityREITIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">FTSE NAREIT All Equity REIT Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_FTSENAREITAllEquityREITIndexreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_FTSENAREITAllEquityREITIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">FTSE NAREIT All Equity REIT Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_FTSENAREITAllEquityREITIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_FTSENAREITAllEquityREITIndexreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_FTSENAREITAllEquityREITIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0000898745_FTSENAREITAllEquityREITIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_Russell1000GrowthIndexreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_Russell1000GrowthIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Russell 1000 Growth Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_Russell1000GrowthIndexreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_Russell1000GrowthIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Russell 1000 Growth Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_Russell1000GrowthIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_Russell1000GrowthIndexreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_Russell1000GrowthIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0000898745_Russell1000GrowthIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000159888Member_label_en-US" xlink:label="lab_ck0000898745_C000159888Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2020 Fund, R-6 [Member]</link:label>
    <link:label id="lab_ck0000898745_C000159888Member_documentation_en-US" xlink:label="lab_ck0000898745_C000159888Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2020 Fund, R-6, C000159888, PLTTX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000159888Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000159888Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000159888Member" xlink:to="lab_ck0000898745_C000159888Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000018958Member_label_en-US" xlink:label="lab_ck0000898745_C000018958Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Core Plus Bond Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000018958Member_documentation_en-US" xlink:label="lab_ck0000898745_C000018958Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Core Plus Bond Fund, Class R-3, C000018958, PBMMX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000018958Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000018958Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000018958Member" xlink:to="lab_ck0000898745_C000018958Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038748Member_label_en-US" xlink:label="lab_ck0000898745_C000038748Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">High Yield Fund, Class A</link:label>
    <link:label id="lab_ck0000898745_C000038748Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038748Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">High Yield Fund, Class A, C000038748, CPHYX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038748Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038748Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038748Member" xlink:to="lab_ck0000898745_C000038748Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000175484Member_label_en-US" xlink:label="lab_ck0000898745_C000175484Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">International Equity Fund, Class R-6</link:label>
    <link:label id="lab_ck0000898745_C000175484Member_documentation_en-US" xlink:label="lab_ck0000898745_C000175484Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">International Equity Fund, Class R-6, C000175484</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000175484Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000175484Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000175484Member" xlink:to="lab_ck0000898745_C000175484Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_RedemptionAndLargeTransactionRiskMember_label_en-US" xlink:label="lab_ck0000898745_RedemptionAndLargeTransactionRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Redemption And Large Transaction Risk Member</link:label>
    <link:label id="lab_ck0000898745_RedemptionAndLargeTransactionRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_RedemptionAndLargeTransactionRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Redemption And Large Transaction Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_RedemptionAndLargeTransactionRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_RedemptionAndLargeTransactionRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_RedemptionAndLargeTransactionRiskMember" xlink:to="lab_ck0000898745_RedemptionAndLargeTransactionRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000022106Member_label_en-US" xlink:label="lab_ck0000898745_S000022106Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2045 Fund</link:label>
    <link:label id="lab_ck0000898745_S000022106Member_documentation_en-US" xlink:label="lab_ck0000898745_S000022106Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2045 Fund, S000022106</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000022106Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000022106Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000022106Member" xlink:to="lab_ck0000898745_S000022106Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019719Member_label_en-US" xlink:label="lab_ck0000898745_C000019719Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SmallCap S&amp;P 600 Index Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000019719Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019719Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SmallCap S&amp;P 600 Index Fund, Institutional Class, C000019719, PSSIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019719Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019719Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019719Member" xlink:to="lab_ck0000898745_C000019719Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000039346Member_label_en-US" xlink:label="lab_ck0000898745_C000039346Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Conservative Growth Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000039346Member_documentation_en-US" xlink:label="lab_ck0000898745_C000039346Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Conservative Growth Fund, Class R-3, C000039346, PCGPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000039346Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000039346Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000039346Member" xlink:to="lab_ck0000898745_C000039346Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_FixedIncomeSecuritiesRiskMember_label_en-US" xlink:label="lab_ck0000898745_FixedIncomeSecuritiesRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fixed-Income Securities Risk Member</link:label>
    <link:label id="lab_ck0000898745_FixedIncomeSecuritiesRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_FixedIncomeSecuritiesRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Fixed-Income Securities Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_FixedIncomeSecuritiesRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_FixedIncomeSecuritiesRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_FixedIncomeSecuritiesRiskMember" xlink:to="lab_ck0000898745_FixedIncomeSecuritiesRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000058847Member_label_en-US" xlink:label="lab_ck0000898745_S000058847Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2065 Fund</link:label>
    <link:label id="lab_ck0000898745_S000058847Member_documentation_en-US" xlink:label="lab_ck0000898745_S000058847Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2065 S000058847</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000058847Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000058847Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000058847Member" xlink:to="lab_ck0000898745_S000058847Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000019119Member_label_en-US" xlink:label="lab_ck0000898745_S000019119Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Global Real Estate Securities Fund</link:label>
    <link:label id="lab_ck0000898745_S000019119Member_documentation_en-US" xlink:label="lab_ck0000898745_S000019119Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Global Real Estate Securities Fund, S000019119</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000019119Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000019119Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000019119Member" xlink:to="lab_ck0000898745_S000019119Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000123726Member_label_en-US" xlink:label="lab_ck0000898745_C000123726Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2060 Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000123726Member_documentation_en-US" xlink:label="lab_ck0000898745_C000123726Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2060 Fund, Class R-5, C000123726</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000123726Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000123726Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000123726Member" xlink:to="lab_ck0000898745_C000123726Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038732Member_label_en-US" xlink:label="lab_ck0000898745_C000038732Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Strategic Growth Fund, Class C</link:label>
    <link:label id="lab_ck0000898745_C000038732Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038732Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Strategic Growth Fund, Class C, C000038732, SWHCX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038732Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038732Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038732Member" xlink:to="lab_ck0000898745_C000038732Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_FundOfFundsRiskMember_label_en-US" xlink:label="lab_ck0000898745_FundOfFundsRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fund Of Funds Risk Member</link:label>
    <link:label id="lab_ck0000898745_FundOfFundsRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_FundOfFundsRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Fund Of Funds Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_FundOfFundsRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_FundOfFundsRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_FundOfFundsRiskMember" xlink:to="lab_ck0000898745_FundOfFundsRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019317Member_label_en-US" xlink:label="lab_ck0000898745_C000019317Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MidCap Fund, Class A</link:label>
    <link:label id="lab_ck0000898745_C000019317Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019317Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MidCap Fund, Class A, C000019317, PEMGX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019317Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019317Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019317Member" xlink:to="lab_ck0000898745_C000019317Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000014232Member_label_en-US" xlink:label="lab_ck0000898745_S000014232Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">California Municipal Fund</link:label>
    <link:label id="lab_ck0000898745_S000014232Member_documentation_en-US" xlink:label="lab_ck0000898745_S000014232Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">California Municipal Fund, S000014232</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000014232Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000014232Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000014232Member" xlink:to="lab_ck0000898745_S000014232Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019805Member_label_en-US" xlink:label="lab_ck0000898745_C000019805Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SmallCap Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000019805Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019805Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SmallCap Fund, Class R-5, C000019805, PSBPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019805Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019805Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019805Member" xlink:to="lab_ck0000898745_C000019805Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019169Member_label_en-US" xlink:label="lab_ck0000898745_C000019169Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">LargeCap S&amp;P 500 Index Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000019169Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019169Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">LargeCap S&amp;P 500 Index Fund, Class R-3, C000019169, PLFMX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019169Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019169Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019169Member" xlink:to="lab_ck0000898745_C000019169Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038718Member_label_en-US" xlink:label="lab_ck0000898745_C000038718Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Conservative Balanced Fund, Class A</link:label>
    <link:label id="lab_ck0000898745_C000038718Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038718Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Conservative Balanced Fund, Class A, C000038718, SAIPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038718Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038718Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038718Member" xlink:to="lab_ck0000898745_C000038718Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_JPMGBI-EMGlobalDiversifiedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_JPMGBI-EMGlobalDiversifiedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">JPM GBI-EM Global Diversified Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_JPMGBI-EMGlobalDiversifiedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_JPMGBI-EMGlobalDiversifiedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">JPM GBI-EM Global Diversified Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_JPMGBI-EMGlobalDiversifiedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_JPMGBI-EMGlobalDiversifiedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_JPMGBI-EMGlobalDiversifiedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:to="lab_ck0000898745_JPMGBI-EMGlobalDiversifiedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000039365Member_label_en-US" xlink:label="lab_ck0000898745_C000039365Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Balanced Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000039365Member_documentation_en-US" xlink:label="lab_ck0000898745_C000039365Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Balanced Fund, Class J, C000039365, PSAJX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000039365Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000039365Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000039365Member" xlink:to="lab_ck0000898745_C000039365Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019312Member_label_en-US" xlink:label="lab_ck0000898745_C000019312Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MidCap Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000019312Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019312Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MidCap Fund, Class R-3, C000019312, PMBMX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019312Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019312Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019312Member" xlink:to="lab_ck0000898745_C000019312Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000014245Member_label_en-US" xlink:label="lab_ck0000898745_S000014245Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Short-Term Income Fund</link:label>
    <link:label id="lab_ck0000898745_S000014245Member_documentation_en-US" xlink:label="lab_ck0000898745_S000014245Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Short-Term Income Fund, S000014245</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000014245Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000014245Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000014245Member" xlink:to="lab_ck0000898745_S000014245Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000007208Member_label_en-US" xlink:label="lab_ck0000898745_S000007208Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2030 Fund</link:label>
    <link:label id="lab_ck0000898745_S000007208Member_documentation_en-US" xlink:label="lab_ck0000898745_S000007208Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2030 Fund, S000007208</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000007208Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000007208Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000007208Member" xlink:to="lab_ck0000898745_S000007208Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_SandP1500reflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_SandP1500reflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">S&amp;P 1500 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_SandP1500reflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_SandP1500reflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">S&amp;P 1500 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_SandP1500reflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_SandP1500reflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_SandP1500reflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0000898745_SandP1500reflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000193006Member_label_en-US" xlink:label="lab_ck0000898745_C000193006Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2065, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000193006Member_documentation_en-US" xlink:label="lab_ck0000898745_C000193006Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2065, Class R-5, C000193006</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000193006Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000193006Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000193006Member" xlink:to="lab_ck0000898745_C000193006Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000170736Member_label_en-US" xlink:label="lab_ck0000898745_C000170736Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finisterre Emerging Markets Total Return Bond Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000170736Member_documentation_en-US" xlink:label="lab_ck0000898745_C000170736Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Finisterre Emerging Markets Total Return Bond Fund, Institutional Class, C000170736</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000170736Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000170736Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000170736Member" xlink:to="lab_ck0000898745_C000170736Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000046553Member_label_en-US" xlink:label="lab_ck0000898745_S000046553Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid Income Fund</link:label>
    <link:label id="lab_ck0000898745_S000046553Member_documentation_en-US" xlink:label="lab_ck0000898745_S000046553Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid Income Fund, S000046553</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000046553Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000046553Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000046553Member" xlink:to="lab_ck0000898745_S000046553Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_BloombergUS.AggregateIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_BloombergUS.AggregateIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Bloomberg US. Aggregate Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_BloombergUS.AggregateIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_BloombergUS.AggregateIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Bloomberg US. Aggregate Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_BloombergUS.AggregateIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_BloombergUS.AggregateIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_BloombergUS.AggregateIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:to="lab_ck0000898745_BloombergUS.AggregateIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000101728Member_label_en-US" xlink:label="lab_ck0000898745_S000101728Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">International Bond Fund</link:label>
    <link:label id="lab_ck0000898745_S000101728Member_documentation_en-US" xlink:label="lab_ck0000898745_S000101728Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">International Bond Fund ,S000101728</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000101728Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000101728Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000101728Member" xlink:to="lab_ck0000898745_S000101728Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019754Member_label_en-US" xlink:label="lab_ck0000898745_C000019754Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2030 Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000019754Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019754Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2030 Fund, Institutional Class, C000019754, PMTIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019754Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019754Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019754Member" xlink:to="lab_ck0000898745_C000019754Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_BloombergMunicipalBondIndexreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_BloombergMunicipalBondIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Bloomberg Municipal Bond Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_BloombergMunicipalBondIndexreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_BloombergMunicipalBondIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Bloomberg Municipal Bond Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_BloombergMunicipalBondIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_BloombergMunicipalBondIndexreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_BloombergMunicipalBondIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0000898745_BloombergMunicipalBondIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000046561Member_label_en-US" xlink:label="lab_ck0000898745_S000046561Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2040 Fund</link:label>
    <link:label id="lab_ck0000898745_S000046561Member_documentation_en-US" xlink:label="lab_ck0000898745_S000046561Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2040 Fund, S000046561</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000046561Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000046561Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000046561Member" xlink:to="lab_ck0000898745_S000046561Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038802Member_label_en-US" xlink:label="lab_ck0000898745_C000038802Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Real Estate Securities Fund, Class C</link:label>
    <link:label id="lab_ck0000898745_C000038802Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038802Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Real Estate Securities Fund, Class C, C000038802, PRCEX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038802Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038802Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038802Member" xlink:to="lab_ck0000898745_C000038802Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_CommercialPaperRiskMember_label_en-US" xlink:label="lab_ck0000898745_CommercialPaperRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Commercial Paper Risk Member</link:label>
    <link:label id="lab_ck0000898745_CommercialPaperRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_CommercialPaperRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Commercial Paper Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_CommercialPaperRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_CommercialPaperRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_CommercialPaperRiskMember" xlink:to="lab_ck0000898745_CommercialPaperRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000199315Member_label_en-US" xlink:label="lab_ck0000898745_C000199315Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid Income Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000199315Member_documentation_en-US" xlink:label="lab_ck0000898745_C000199315Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid Income Fund, Class J, C000199315</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000199315Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000199315Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000199315Member" xlink:to="lab_ck0000898745_C000199315Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000007173Member_label_en-US" xlink:label="lab_ck0000898745_S000007173Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MidCap Value Fund I</link:label>
    <link:label id="lab_ck0000898745_S000007173Member_documentation_en-US" xlink:label="lab_ck0000898745_S000007173Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MidCap Value Fund I, S000007173</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000007173Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000007173Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000007173Member" xlink:to="lab_ck0000898745_S000007173Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_BloombergUSAgencyFixedRateMBSIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_BloombergUSAgencyFixedRateMBSIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Bloomberg U.S. Agency Fixed Rate MBS Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_BloombergUSAgencyFixedRateMBSIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_BloombergUSAgencyFixedRateMBSIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Bloomberg U.S. Agency Fixed Rate MBS Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_BloombergUSAgencyFixedRateMBSIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_BloombergUSAgencyFixedRateMBSIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_BloombergUSAgencyFixedRateMBSIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:to="lab_ck0000898745_BloombergUSAgencyFixedRateMBSIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_BloombergUSTreasuryBellwethersThreeMonthIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_BloombergUSTreasuryBellwethersThreeMonthIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Bloomberg U.S. Treasury Bellwethers 3 Month Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_BloombergUSTreasuryBellwethersThreeMonthIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_BloombergUSTreasuryBellwethersThreeMonthIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Bloomberg U.S. Treasury Bellwethers 3 Month Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_BloombergUSTreasuryBellwethersThreeMonthIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_BloombergUSTreasuryBellwethersThreeMonthIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_BloombergUSTreasuryBellwethersThreeMonthIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:to="lab_ck0000898745_BloombergUSTreasuryBellwethersThreeMonthIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_PassiveStrategyRiskMember_label_en-US" xlink:label="lab_ck0000898745_PassiveStrategyRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Passive Strategy Risk Member</link:label>
    <link:label id="lab_ck0000898745_PassiveStrategyRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_PassiveStrategyRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Passive Strategy Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_PassiveStrategyRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_PassiveStrategyRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_PassiveStrategyRiskMember" xlink:to="lab_ck0000898745_PassiveStrategyRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000085768Member_label_en-US" xlink:label="lab_ck0000898745_C000085768Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Core Fixed Income Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000085768Member_documentation_en-US" xlink:label="lab_ck0000898745_C000085768Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Core Fixed Income Fund, Class R-5 Shares, C000085768, PIOQX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000085768Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000085768Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000085768Member" xlink:to="lab_ck0000898745_C000085768Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000071805Member_label_en-US" xlink:label="lab_ck0000898745_C000071805Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Diversified Income Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000071805Member_documentation_en-US" xlink:label="lab_ck0000898745_C000071805Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Diversified Income Fund, Institutional Class, C000071805, PGDIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000071805Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000071805Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000071805Member" xlink:to="lab_ck0000898745_C000071805Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_IndustryConcentrationRiskMember_label_en-US" xlink:label="lab_ck0000898745_IndustryConcentrationRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Industry Concentration Risk Member</link:label>
    <link:label id="lab_ck0000898745_IndustryConcentrationRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_IndustryConcentrationRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Industry Concentration Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_IndustryConcentrationRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_IndustryConcentrationRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_IndustryConcentrationRiskMember" xlink:to="lab_ck0000898745_IndustryConcentrationRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_IndustrialRevenueBondRiskMember_label_en-US" xlink:label="lab_ck0000898745_IndustrialRevenueBondRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Industrial Revenue Bond Risk Member</link:label>
    <link:label id="lab_ck0000898745_IndustrialRevenueBondRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_IndustrialRevenueBondRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Industrial Revenue Bond Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_IndustrialRevenueBondRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_IndustrialRevenueBondRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_IndustrialRevenueBondRiskMember" xlink:to="lab_ck0000898745_IndustrialRevenueBondRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000007203Member_label_en-US" xlink:label="lab_ck0000898745_S000007203Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SmallCap S&amp;P 600 Index Fund</link:label>
    <link:label id="lab_ck0000898745_S000007203Member_documentation_en-US" xlink:label="lab_ck0000898745_S000007203Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SmallCap S&amp;P 600 Index Fund, S000007203</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000007203Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000007203Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000007203Member" xlink:to="lab_ck0000898745_S000007203Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000196721Member_label_en-US" xlink:label="lab_ck0000898745_C000196721Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Government Money Market Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000196721Member_documentation_en-US" xlink:label="lab_ck0000898745_C000196721Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Government Money Market Fund Institutional C000196721Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000196721Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000196721Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000196721Member" xlink:to="lab_ck0000898745_C000196721Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000090498Member_label_en-US" xlink:label="lab_ck0000898745_C000090498Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Short-Term Income Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000090498Member_documentation_en-US" xlink:label="lab_ck0000898745_C000090498Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Short-Term Income Fund, Class R-5 Shares, C000090498, PSIQX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000090498Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000090498Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000090498Member" xlink:to="lab_ck0000898745_C000090498Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000167007Member_label_en-US" xlink:label="lab_ck0000898745_C000167007Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Global Real Estate Securities Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000167007Member_documentation_en-US" xlink:label="lab_ck0000898745_C000167007Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Global Real Estate Securities Fund, Class R-5, C000167007</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000167007Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000167007Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000167007Member" xlink:to="lab_ck0000898745_C000167007Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000014240Member_label_en-US" xlink:label="lab_ck0000898745_S000014240Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equity Income Fund</link:label>
    <link:label id="lab_ck0000898745_S000014240Member_documentation_en-US" xlink:label="lab_ck0000898745_S000014240Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Equity Income Fund, S000014240</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000014240Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000014240Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000014240Member" xlink:to="lab_ck0000898745_S000014240Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019170Member_label_en-US" xlink:label="lab_ck0000898745_C000019170Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">LargeCap S&amp;P 500 Index Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000019170Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019170Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">LargeCap S&amp;P 500 Index Fund, Class R-5, C000019170, PLFPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019170Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019170Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019170Member" xlink:to="lab_ck0000898745_C000019170Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019333Member_label_en-US" xlink:label="lab_ck0000898745_C000019333Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">LargeCap Growth Fund I, Class A</link:label>
    <link:label id="lab_ck0000898745_C000019333Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019333Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">LargeCap Growth I Fund, Class A, C000019333</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019333Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019333Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019333Member" xlink:to="lab_ck0000898745_C000019333Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019373Member_label_en-US" xlink:label="lab_ck0000898745_C000019373Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">International Equity Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000019373Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019373Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">International Equity Fund, Class R-5, C000019373, PTPPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019373Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019373Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019373Member" xlink:to="lab_ck0000898745_C000019373Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000079799Member_label_en-US" xlink:label="lab_ck0000898745_S000079799Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2070 Fund</link:label>
    <link:label id="lab_ck0000898745_S000079799Member_documentation_en-US" xlink:label="lab_ck0000898745_S000079799Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2070 Fund, S000079799</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000079799Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000079799Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000079799Member" xlink:to="lab_ck0000898745_S000079799Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000039341Member_label_en-US" xlink:label="lab_ck0000898745_C000039341Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Conservative Balanced Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000039341Member_documentation_en-US" xlink:label="lab_ck0000898745_C000039341Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Conservative Balanced Fund, Class J, C000039341, PCBJX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000039341Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000039341Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000039341Member" xlink:to="lab_ck0000898745_C000039341Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019756Member_label_en-US" xlink:label="lab_ck0000898745_C000019756Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2030 Fund, Class A</link:label>
    <link:label id="lab_ck0000898745_C000019756Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019756Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2030 Fund, Class A, C000019756, PTCAX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019756Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019756Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019756Member" xlink:to="lab_ck0000898745_C000019756Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000199317Member_label_en-US" xlink:label="lab_ck0000898745_C000199317Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2060 Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000199317Member_documentation_en-US" xlink:label="lab_ck0000898745_C000199317Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2060 Fund, Class J, C000199317</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000199317Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000199317Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000199317Member" xlink:to="lab_ck0000898745_C000199317Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000063433Member_label_en-US" xlink:label="lab_ck0000898745_C000063433Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2025 Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000063433Member_documentation_en-US" xlink:label="lab_ck0000898745_C000063433Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2025 Fund, Class R-5, C000063433, LTPDX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000063433Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000063433Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000063433Member" xlink:to="lab_ck0000898745_C000063433Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019376Member_label_en-US" xlink:label="lab_ck0000898745_C000019376Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">International Equity Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000019376Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019376Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">International Equity Fund, Institutional Class, C000019376, PINIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019376Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019376Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019376Member" xlink:to="lab_ck0000898745_C000019376Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019628Member_label_en-US" xlink:label="lab_ck0000898745_C000019628Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SmallCap Growth I Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000019628Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019628Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SmallCap Growth I Fund, Class R-5, C000019628, PPNPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019628Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019628Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019628Member" xlink:to="lab_ck0000898745_C000019628Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000063443Member_label_en-US" xlink:label="lab_ck0000898745_C000063443Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2045 Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000063443Member_documentation_en-US" xlink:label="lab_ck0000898745_C000063443Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2045 Fund, Class R-5, C000063443, LTRDX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000063443Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000063443Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000063443Member" xlink:to="lab_ck0000898745_C000063443Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_AssetAllocationRiskMember_label_en-US" xlink:label="lab_ck0000898745_AssetAllocationRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Asset Allocation Risk Member</link:label>
    <link:label id="lab_ck0000898745_AssetAllocationRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_AssetAllocationRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Asset Allocation Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_AssetAllocationRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_AssetAllocationRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_AssetAllocationRiskMember" xlink:to="lab_ck0000898745_AssetAllocationRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019743Member_label_en-US" xlink:label="lab_ck0000898745_C000019743Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2020 Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000019743Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019743Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2020 Fund, Class R-5, C000019743, PTBPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019743Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019743Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019743Member" xlink:to="lab_ck0000898745_C000019743Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000069149Member_label_en-US" xlink:label="lab_ck0000898745_C000069149Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Overseas Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000069149Member_documentation_en-US" xlink:label="lab_ck0000898745_C000069149Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Overseas Fund, Institutional Class, C000069149, PINZX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000069149Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000069149Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000069149Member" xlink:to="lab_ck0000898745_C000069149Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019464Member_label_en-US" xlink:label="lab_ck0000898745_C000019464Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">LargeCap Value Fund III, Class J</link:label>
    <link:label id="lab_ck0000898745_C000019464Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019464Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">LargeCap Value III Fund, Class J, C000019464, PLVJX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019464Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019464Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019464Member" xlink:to="lab_ck0000898745_C000019464Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019081Member_label_en-US" xlink:label="lab_ck0000898745_C000019081Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inflation Protection Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000019081Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019081Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Inflation Protection Fund, Class R-3, C000019081, PIFPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019081Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019081Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019081Member" xlink:to="lab_ck0000898745_C000019081Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000076717Member_label_en-US" xlink:label="lab_ck0000898745_C000076717Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SmallCap Value II Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000076717Member_documentation_en-US" xlink:label="lab_ck0000898745_C000076717Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SmallCap Value II Fund, Class J, C000076717, PSMJX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000076717Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000076717Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000076717Member" xlink:to="lab_ck0000898745_C000076717Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038729Member_label_en-US" xlink:label="lab_ck0000898745_C000038729Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Flexible Income Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000038729Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038729Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Flexible Income Fund, Institutional Class, C000038729, PIFIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038729Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038729Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038729Member" xlink:to="lab_ck0000898745_C000038729Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_HighYieldSecuritiesRiskMember_label_en-US" xlink:label="lab_ck0000898745_HighYieldSecuritiesRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">High Yield Securities Risk Member</link:label>
    <link:label id="lab_ck0000898745_HighYieldSecuritiesRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_HighYieldSecuritiesRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">High Yield Securities Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_HighYieldSecuritiesRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_HighYieldSecuritiesRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_HighYieldSecuritiesRiskMember" xlink:to="lab_ck0000898745_HighYieldSecuritiesRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000145323Member_label_en-US" xlink:label="lab_ck0000898745_C000145323Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2035 Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000145323Member_documentation_en-US" xlink:label="lab_ck0000898745_C000145323Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2035 Fund, Institutional Class, C000145323, PHTJX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000145323Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000145323Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000145323Member" xlink:to="lab_ck0000898745_C000145323Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019720Member_label_en-US" xlink:label="lab_ck0000898745_C000019720Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SmallCap S&amp;P 600 Index Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000019720Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019720Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SmallCap S&amp;P 600 Index Fund, Class J, C000019720, PSSJX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019720Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019720Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019720Member" xlink:to="lab_ck0000898745_C000019720Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000241179Member_label_en-US" xlink:label="lab_ck0000898745_C000241179Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2070 Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000241179Member_documentation_en-US" xlink:label="lab_ck0000898745_C000241179Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Series S000079799 Principal LifeTime 2070 Fund Class/Contract C000241179 R-3 PLTDX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000241179Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000241179Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000241179Member" xlink:to="lab_ck0000898745_C000241179Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019054Member_label_en-US" xlink:label="lab_ck0000898745_C000019054Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Diversified International Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000019054Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019054Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Diversified International Fund, Class R-3, C000019054, PINRX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019054Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019054Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019054Member" xlink:to="lab_ck0000898745_C000019054Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000085771Member_label_en-US" xlink:label="lab_ck0000898745_C000085771Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Core Fixed Income Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000085771Member_documentation_en-US" xlink:label="lab_ck0000898745_C000085771Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Core Fixed Income Fund, Class R-3 Shares, C000085771, PIOOX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000085771Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000085771Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000085771Member" xlink:to="lab_ck0000898745_C000085771Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000145320Member_label_en-US" xlink:label="lab_ck0000898745_C000145320Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2030 Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000145320Member_documentation_en-US" xlink:label="lab_ck0000898745_C000145320Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2030 Fund, Institutional Class, C000145320, PHTNX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000145320Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000145320Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000145320Member" xlink:to="lab_ck0000898745_C000145320Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038766Member_label_en-US" xlink:label="lab_ck0000898745_C000038766Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Short-Term Income Fund, Class C</link:label>
    <link:label id="lab_ck0000898745_C000038766Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038766Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Short-Term Income Fund, Class C, C000038766, STCCX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038766Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038766Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038766Member" xlink:to="lab_ck0000898745_C000038766Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000199321Member_label_en-US" xlink:label="lab_ck0000898745_C000199321Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2030 Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000199321Member_documentation_en-US" xlink:label="lab_ck0000898745_C000199321Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2030 Fund, Class J, C000199321</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000199321Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000199321Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000199321Member" xlink:to="lab_ck0000898745_C000199321Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019346Member_label_en-US" xlink:label="lab_ck0000898745_C000019346Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MidCap S&amp;P 400 Index Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000019346Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019346Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MidCap S&amp;P 400 Index Fund, Class R-5, C000019346, PMFPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019346Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019346Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019346Member" xlink:to="lab_ck0000898745_C000019346Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000039359Member_label_en-US" xlink:label="lab_ck0000898745_C000039359Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Strategic Growth Fund, Class J [Member]</link:label>
    <link:label id="lab_ck0000898745_C000039359Member_documentation_en-US" xlink:label="lab_ck0000898745_C000039359Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Strategic Growth Fund, Class J, C000039359, PSWJX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000039359Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000039359Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000039359Member" xlink:to="lab_ck0000898745_C000039359Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019791Member_label_en-US" xlink:label="lab_ck0000898745_C000019791Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Real Estate Securities Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000019791Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019791Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Real Estate Securities, Class J, C000019791, PREJX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019791Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019791Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019791Member" xlink:to="lab_ck0000898745_C000019791Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000063429Member_label_en-US" xlink:label="lab_ck0000898745_C000063429Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2025 Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000063429Member_documentation_en-US" xlink:label="lab_ck0000898745_C000063429Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2025 Fund, Institutional Class, C000063429, LTSTX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000063429Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000063429Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000063429Member" xlink:to="lab_ck0000898745_C000063429Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000007013Member_label_en-US" xlink:label="lab_ck0000898745_S000007013Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Global Emerging Markets Fund</link:label>
    <link:label id="lab_ck0000898745_S000007013Member_documentation_en-US" xlink:label="lab_ck0000898745_S000007013Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Global Emerging Markets Fund, S000007013</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000007013Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000007013Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000007013Member" xlink:to="lab_ck0000898745_S000007013Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038740Member_label_en-US" xlink:label="lab_ck0000898745_C000038740Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal Capital Appreciation Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000038740Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038740Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal Capital Appreciation Fund, Institutional Class, C000038740, PWCIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038740Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038740Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038740Member" xlink:to="lab_ck0000898745_C000038740Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000063435Member_label_en-US" xlink:label="lab_ck0000898745_C000063435Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2035 Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000063435Member_documentation_en-US" xlink:label="lab_ck0000898745_C000063435Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2035 Fund, Class R-3, C000063435, LTAOX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000063435Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000063435Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000063435Member" xlink:to="lab_ck0000898745_C000063435Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038737Member_label_en-US" xlink:label="lab_ck0000898745_C000038737Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal Capital Appreciation Fund, Class A</link:label>
    <link:label id="lab_ck0000898745_C000038737Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038737Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal Capital Appreciation Fund, Class A, C000038737, CMNWX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038737Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038737Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038737Member" xlink:to="lab_ck0000898745_C000038737Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000111521Member_label_en-US" xlink:label="lab_ck0000898745_C000111521Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Overseas Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000111521Member_documentation_en-US" xlink:label="lab_ck0000898745_C000111521Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Overseas Fund, Class R-3, C000111521, PINTX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000111521Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000111521Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000111521Member" xlink:to="lab_ck0000898745_C000111521Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_EmergingMarketsRiskFrontierMarketsRiskMember_label_en-US" xlink:label="lab_ck0000898745_EmergingMarketsRiskFrontierMarketsRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Emerging Markets Risk, Frontier Markets Risk Member</link:label>
    <link:label id="lab_ck0000898745_EmergingMarketsRiskFrontierMarketsRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_EmergingMarketsRiskFrontierMarketsRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Emerging Markets Risk, Frontier Markets Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_EmergingMarketsRiskFrontierMarketsRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_EmergingMarketsRiskFrontierMarketsRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_EmergingMarketsRiskFrontierMarketsRiskMember" xlink:to="lab_ck0000898745_EmergingMarketsRiskFrontierMarketsRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019331Member_label_en-US" xlink:label="lab_ck0000898745_C000019331Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">LargeCap Growth Fund I, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000019331Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019331Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">LargeCap Growth I Fund, Institutional Class, C000019331, PLGIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019331Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019331Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019331Member" xlink:to="lab_ck0000898745_C000019331Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019788Member_label_en-US" xlink:label="lab_ck0000898745_C000019788Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Real Estate Securities Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000019788Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019788Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Real Estate Securities, Class R-5, C000019788, PREPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019788Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019788Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019788Member" xlink:to="lab_ck0000898745_C000019788Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000014237Member_label_en-US" xlink:label="lab_ck0000898745_S000014237Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Tax-Exempt Bond Fund</link:label>
    <link:label id="lab_ck0000898745_S000014237Member_documentation_en-US" xlink:label="lab_ck0000898745_S000014237Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Tax-Exempt Bond Fund, S000014237</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000014237Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000014237Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000014237Member" xlink:to="lab_ck0000898745_S000014237Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_DerivativesRiskForwardContractsFuturesAndSwapsRiskMember_label_en-US" xlink:label="lab_ck0000898745_DerivativesRiskForwardContractsFuturesAndSwapsRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Derivatives Risk, Forward Contracts, Futures, And Swaps Risk Member</link:label>
    <link:label id="lab_ck0000898745_DerivativesRiskForwardContractsFuturesAndSwapsRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_DerivativesRiskForwardContractsFuturesAndSwapsRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Derivatives Risk, Forward Contracts, Futures, And Swaps Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_DerivativesRiskForwardContractsFuturesAndSwapsRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_DerivativesRiskForwardContractsFuturesAndSwapsRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_DerivativesRiskForwardContractsFuturesAndSwapsRiskMember" xlink:to="lab_ck0000898745_DerivativesRiskForwardContractsFuturesAndSwapsRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_SAMConservativeGrowthBlendedIndexExceptAsNotedForMSCIEAFEIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_SAMConservativeGrowthBlendedIndexExceptAsNotedForMSCIEAFEIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Conservative Growth Blended Index (except as noted for MSCI EAFE Index NTR, reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_SAMConservativeGrowthBlendedIndexExceptAsNotedForMSCIEAFEIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_SAMConservativeGrowthBlendedIndexExceptAsNotedForMSCIEAFEIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Conservative Growth Blended Index (except as noted for MSCI EAFE Index NTR, reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_SAMConservativeGrowthBlendedIndexExceptAsNotedForMSCIEAFEIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_SAMConservativeGrowthBlendedIndexExceptAsNotedForMSCIEAFEIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_SAMConservativeGrowthBlendedIndexExceptAsNotedForMSCIEAFEIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:to="lab_ck0000898745_SAMConservativeGrowthBlendedIndexExceptAsNotedForMSCIEAFEIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038764Member_label_en-US" xlink:label="lab_ck0000898745_C000038764Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Short-Term Income Fund, Class A</link:label>
    <link:label id="lab_ck0000898745_C000038764Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038764Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Short-Term Income Fund, Class A, C000038764, SRHQX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038764Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038764Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038764Member" xlink:to="lab_ck0000898745_C000038764Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019770Member_label_en-US" xlink:label="lab_ck0000898745_C000019770Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2050 Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000019770Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019770Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2050 Fund, Class R-3, C000019770, PTERX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019770Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019770Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019770Member" xlink:to="lab_ck0000898745_C000019770Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_Russell2000IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_Russell2000IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Russell 2000 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_Russell2000IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_Russell2000IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Russell 2000 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_Russell2000IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_Russell2000IndexreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_Russell2000IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0000898745_Russell2000IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_BloombergCredit13YearsIndexreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_BloombergCredit13YearsIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Bloomberg Credit 1-3 Years Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_BloombergCredit13YearsIndexreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_BloombergCredit13YearsIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Bloomberg Credit 1-3 Years Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_BloombergCredit13YearsIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_BloombergCredit13YearsIndexreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_BloombergCredit13YearsIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0000898745_BloombergCredit13YearsIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_SAMFlexibleIncomeBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_SAMFlexibleIncomeBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Flexible Income Blended Index (except as noted for MSCI ACWI Index NTR, reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_SAMFlexibleIncomeBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_SAMFlexibleIncomeBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Flexible Income Blended Index (except as noted for MSCI ACWI Index NTR, reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_SAMFlexibleIncomeBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_SAMFlexibleIncomeBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_SAMFlexibleIncomeBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:to="lab_ck0000898745_SAMFlexibleIncomeBlendedIndexExceptAsNotedForMSCIACWIIndexNTRReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_Russell2000ValueIndexreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_Russell2000ValueIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Russell 2000 Value Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_Russell2000ValueIndexreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_Russell2000ValueIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Russell 2000 Value Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_Russell2000ValueIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_Russell2000ValueIndexreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_Russell2000ValueIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0000898745_Russell2000ValueIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_RepurchaseAgreementRiskMember_label_en-US" xlink:label="lab_ck0000898745_RepurchaseAgreementRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Repurchase Agreement Risk Member</link:label>
    <link:label id="lab_ck0000898745_RepurchaseAgreementRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_RepurchaseAgreementRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Repurchase Agreement Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_RepurchaseAgreementRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_RepurchaseAgreementRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_RepurchaseAgreementRiskMember" xlink:to="lab_ck0000898745_RepurchaseAgreementRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000193001Member_label_en-US" xlink:label="lab_ck0000898745_C000193001Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2065, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000193001Member_documentation_en-US" xlink:label="lab_ck0000898745_C000193001Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2065, Institutional Class, C000193001</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000193001Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000193001Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000193001Member" xlink:to="lab_ck0000898745_C000193001Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_JPMCEMBIBroadDiversifiedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_JPMCEMBIBroadDiversifiedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">JPM CEMBI Broad Diversified Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_JPMCEMBIBroadDiversifiedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_JPMCEMBIBroadDiversifiedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">JPM CEMBI Broad Diversified Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_JPMCEMBIBroadDiversifiedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_JPMCEMBIBroadDiversifiedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_JPMCEMBIBroadDiversifiedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:to="lab_ck0000898745_JPMCEMBIBroadDiversifiedIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000199323Member_label_en-US" xlink:label="lab_ck0000898745_C000199323Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2040 Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000199323Member_documentation_en-US" xlink:label="lab_ck0000898745_C000199323Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2040 Fund, Class J, C000199323</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000199323Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000199323Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000199323Member" xlink:to="lab_ck0000898745_C000199323Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000085765Member_label_en-US" xlink:label="lab_ck0000898745_C000085765Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equity Income Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000085765Member_documentation_en-US" xlink:label="lab_ck0000898745_C000085765Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Equity Income Fund, Class R-3 Shares, C000085765, PEIOX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000085765Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000085765Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000085765Member" xlink:to="lab_ck0000898745_C000085765Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_EquitySecuritiesRiskGrowthStyleRiskMember_label_en-US" xlink:label="lab_ck0000898745_EquitySecuritiesRiskGrowthStyleRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equity Securities Risk, Growth Style Risk Member</link:label>
    <link:label id="lab_ck0000898745_EquitySecuritiesRiskGrowthStyleRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_EquitySecuritiesRiskGrowthStyleRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Equity Securities Risk, Growth Style Risk Member</link:label>
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    <link:label id="lab_ck0000898745_C000019764Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019764Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2040 Fund, Class J, C000019764, PTDJX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019764Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019764Member"/>
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    <link:label id="lab_ck0000898745_C000071808Member_documentation_en-US" xlink:label="lab_ck0000898745_C000071808Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Diversified Income Fund, Class C, C000071808, PGDCX</link:label>
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    <link:label id="lab_ck0000898745_C000038770Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038770Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Balanced Fund, Class C, C000038770, SCBPX</link:label>
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    <link:label id="lab_ck0000898745_S000007211Member_documentation_en-US" xlink:label="lab_ck0000898745_S000007211Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Strategic Income Fund, S000007211</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000007211Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000007211Member"/>
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    <link:label id="lab_ck0000898745_BloombergGlobalAggregateIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_BloombergGlobalAggregateIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Bloomberg Global Aggregate Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_BloombergGlobalAggregateIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_BloombergGlobalAggregateIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember"/>
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    <link:label id="lab_ck0000898745_C000019631Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019631Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SmallCap Growth I Fund, Class J, C000019631, PSIJX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019631Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019631Member"/>
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    <link:label id="lab_ck0000898745_C000063441Member_documentation_en-US" xlink:label="lab_ck0000898745_C000063441Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2045 Fund, Class R-3, C000063441, LTRVX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000063441Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000063441Member"/>
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    <link:label id="lab_ck0000898745_InvestmentCompanySecuritiesRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_InvestmentCompanySecuritiesRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Investment Company Securities Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_InvestmentCompanySecuritiesRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_InvestmentCompanySecuritiesRiskMember"/>
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    <link:label id="lab_ck0000898745_EquitySecuritiesRiskMember_label_en-US" xlink:label="lab_ck0000898745_EquitySecuritiesRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equity Securities Risk Member</link:label>
    <link:label id="lab_ck0000898745_EquitySecuritiesRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_EquitySecuritiesRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Equity Securities Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_EquitySecuritiesRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_EquitySecuritiesRiskMember"/>
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    <link:label id="lab_ck0000898745_C000241178Member_documentation_en-US" xlink:label="lab_ck0000898745_C000241178Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Series S000079799 Principal LifeTime 2070 Fund Class/Contract C000241178 R-5 PLTFX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000241178Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000241178Member"/>
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    <link:label id="lab_ck0000898745_ConvertibleSecuritiesRiskMember_label_en-US" xlink:label="lab_ck0000898745_ConvertibleSecuritiesRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Convertible Securities Risk Member</link:label>
    <link:label id="lab_ck0000898745_ConvertibleSecuritiesRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_ConvertibleSecuritiesRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Convertible Securities Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_ConvertibleSecuritiesRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_ConvertibleSecuritiesRiskMember"/>
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    <link:label id="lab_ck0000898745_C000038722Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038722Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Conservative Growth Fund, Class A, C000038722, SAGPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038722Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038722Member"/>
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    <link:label id="lab_ck0000898745_BloombergUSTreasuryTIPSIndexreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_BloombergUSTreasuryTIPSIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Bloomberg US Treasury TIPS Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_BloombergUSTreasuryTIPSIndexreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_BloombergUSTreasuryTIPSIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Bloomberg US Treasury TIPS Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_BloombergUSTreasuryTIPSIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_BloombergUSTreasuryTIPSIndexreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
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    <link:label id="lab_ck0000898745_C000019752Member_label_en-US" xlink:label="lab_ck0000898745_C000019752Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2030 Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000019752Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019752Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2030 Fund, Class R-5, C000019752, PTCPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019752Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019752Member"/>
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    <link:label id="lab_ck0000898745_Russell2000GrowthIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_Russell2000GrowthIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Russell2000GrowthIndexreflectsnodeductionforfeesexpensesortaxes</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_Russell2000GrowthIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_Russell2000GrowthIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember"/>
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    <link:label id="lab_ck0000898745_C000063437Member_documentation_en-US" xlink:label="lab_ck0000898745_C000063437Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2035 Fund, Class R-5, C000063437, LTPEX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000063437Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000063437Member"/>
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    <link:label id="lab_ck0000898745_C000019146Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019146Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Global Emerging Markets Fund, Class A, C000019146, PRIAX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019146Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019146Member"/>
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    <link:label id="lab_ck0000898745_S000006992Member_label_en-US" xlink:label="lab_ck0000898745_S000006992Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Diversified International Fund</link:label>
    <link:label id="lab_ck0000898745_S000006992Member_documentation_en-US" xlink:label="lab_ck0000898745_S000006992Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Diversified International Fund, S000006992</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000006992Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000006992Member"/>
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    <link:label id="lab_ck0000898745_C000019808Member_label_en-US" xlink:label="lab_ck0000898745_C000019808Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SmallCap Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000019808Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019808Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SmallCap Fund, Class J, C000019808, PSBJX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019808Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019808Member"/>
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    <link:label id="lab_ck0000898745_S000007077Member_documentation_en-US" xlink:label="lab_ck0000898745_S000007077Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">LargeCap Growth Fund I, S000007077</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000007077Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000007077Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000007077Member" xlink:to="lab_ck0000898745_S000007077Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000241172Member_label_en-US" xlink:label="lab_ck0000898745_C000241172Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2070 Fund Class J</link:label>
    <link:label id="lab_ck0000898745_C000241172Member_documentation_en-US" xlink:label="lab_ck0000898745_C000241172Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2070 Fund Class J , C000241172</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000241172Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000241172Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000241172Member" xlink:to="lab_ck0000898745_C000241172Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_Russell1000IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_Russell1000IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Russell 1000 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_Russell1000IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_Russell1000IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Russell 1000 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_Russell1000IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_Russell1000IndexreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_Russell1000IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0000898745_Russell1000IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000149259Member_label_en-US" xlink:label="lab_ck0000898745_C000149259Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SmallCap Value Fund II, Class R-6</link:label>
    <link:label id="lab_ck0000898745_C000149259Member_documentation_en-US" xlink:label="lab_ck0000898745_C000149259Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SmallCap Value Fund II, Class R-6 Shares, C000149259, PSMVX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000149259Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000149259Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000149259Member" xlink:to="lab_ck0000898745_C000149259Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000000000Member_label_en-US" xlink:label="lab_ck0000898745_C000000000Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Government Money Market Fund Class R-6</link:label>
    <link:label id="lab_ck0000898745_C000000000Member_documentation_en-US" xlink:label="lab_ck0000898745_C000000000Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Government Money Market Fund Class R-6</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000000000Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000000000Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000000000Member" xlink:to="lab_ck0000898745_C000000000Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_EquitySecuritiesRiskValueStyleRiskMember_label_en-US" xlink:label="lab_ck0000898745_EquitySecuritiesRiskValueStyleRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equity Securities Risk, Value Style Risk Member</link:label>
    <link:label id="lab_ck0000898745_EquitySecuritiesRiskValueStyleRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_EquitySecuritiesRiskValueStyleRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Equity Securities Risk, Value Style Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_EquitySecuritiesRiskValueStyleRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_EquitySecuritiesRiskValueStyleRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_EquitySecuritiesRiskValueStyleRiskMember" xlink:to="lab_ck0000898745_EquitySecuritiesRiskValueStyleRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019627Member_label_en-US" xlink:label="lab_ck0000898745_C000019627Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SmallCap Growth I Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000019627Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019627Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SmallCap Growth I Fund, Class R-3, C000019627, PPNMX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019627Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019627Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019627Member" xlink:to="lab_ck0000898745_C000019627Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000079798Member_label_en-US" xlink:label="lab_ck0000898745_S000079798Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2070 Fund</link:label>
    <link:label id="lab_ck0000898745_S000079798Member_documentation_en-US" xlink:label="lab_ck0000898745_S000079798Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2070 Fund , S000079798</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000079798Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000079798Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000079798Member" xlink:to="lab_ck0000898745_S000079798Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019082Member_label_en-US" xlink:label="lab_ck0000898745_C000019082Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inflation Protection Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000019082Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019082Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Inflation Protection Fund, Class R-5, C000019082, PBPPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019082Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019082Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019082Member" xlink:to="lab_ck0000898745_C000019082Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019589Member_label_en-US" xlink:label="lab_ck0000898745_C000019589Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SmallCap Value II Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000019589Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019589Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SmallCap Value II Fund, Institutional Class, C000019589, PPVIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019589Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019589Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019589Member" xlink:to="lab_ck0000898745_C000019589Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038715Member_label_en-US" xlink:label="lab_ck0000898745_C000038715Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">California Municipal Fund, Class A</link:label>
    <link:label id="lab_ck0000898745_C000038715Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038715Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">California Municipal Fund, Class A, C000038715, SRCMX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038715Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038715Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038715Member" xlink:to="lab_ck0000898745_C000038715Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_CounterpartyRiskMember_label_en-US" xlink:label="lab_ck0000898745_CounterpartyRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Counterparty Risk Member</link:label>
    <link:label id="lab_ck0000898745_CounterpartyRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_CounterpartyRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Counterparty Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_CounterpartyRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_CounterpartyRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_CounterpartyRiskMember" xlink:to="lab_ck0000898745_CounterpartyRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000085760Member_label_en-US" xlink:label="lab_ck0000898745_C000085760Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal Capital Appreciation Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000085760Member_documentation_en-US" xlink:label="lab_ck0000898745_C000085760Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal Capital Appreciation Fund, Class R-3 Shares, C000085760, PCAOX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000085760Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000085760Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000085760Member" xlink:to="lab_ck0000898745_C000085760Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000046556Member_label_en-US" xlink:label="lab_ck0000898745_S000046556Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2015 Fund</link:label>
    <link:label id="lab_ck0000898745_S000046556Member_documentation_en-US" xlink:label="lab_ck0000898745_S000046556Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2015 Fund, S000046556</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000046556Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000046556Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000046556Member" xlink:to="lab_ck0000898745_S000046556Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000052889Member_label_en-US" xlink:label="lab_ck0000898745_C000052889Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Global Real Estate Securities Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000052889Member_documentation_en-US" xlink:label="lab_ck0000898745_C000052889Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Global Real Estate Securities Fund, Institutional Class, C000052889, POSIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000052889Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000052889Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000052889Member" xlink:to="lab_ck0000898745_C000052889Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019140Member_label_en-US" xlink:label="lab_ck0000898745_C000019140Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Global Emerging Markets Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000019140Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019140Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Global Emerging Markets Fund, Class R-3, C000019140, PEAPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019140Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019140Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019140Member" xlink:to="lab_ck0000898745_C000019140Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000063451Member_label_en-US" xlink:label="lab_ck0000898745_C000063451Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2055 Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000063451Member_documentation_en-US" xlink:label="lab_ck0000898745_C000063451Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2055 Fund, Institutional Class, C000063451, LTFIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000063451Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000063451Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000063451Member" xlink:to="lab_ck0000898745_C000063451Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_EmergingMarketsRiskMember_label_en-US" xlink:label="lab_ck0000898745_EmergingMarketsRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Emerging Markets Risk Member</link:label>
    <link:label id="lab_ck0000898745_EmergingMarketsRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_EmergingMarketsRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Emerging Markets Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_EmergingMarketsRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_EmergingMarketsRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_EmergingMarketsRiskMember" xlink:to="lab_ck0000898745_EmergingMarketsRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_FrequentTradingRiskMember_label_en-US" xlink:label="lab_ck0000898745_FrequentTradingRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Frequent Trading Risk Member</link:label>
    <link:label id="lab_ck0000898745_FrequentTradingRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_FrequentTradingRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Frequent Trading Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_FrequentTradingRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_FrequentTradingRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_FrequentTradingRiskMember" xlink:to="lab_ck0000898745_FrequentTradingRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038767Member_label_en-US" xlink:label="lab_ck0000898745_C000038767Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Short-Term Income Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000038767Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038767Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Short-Term Income Fund, Institutional Class, C000038767, PSHIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038767Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038767Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038767Member" xlink:to="lab_ck0000898745_C000038767Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019315Member_label_en-US" xlink:label="lab_ck0000898745_C000019315Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MidCap Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000019315Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019315Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MidCap Fund, Institutional Class, C00019315, PCBIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019315Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019315Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019315Member" xlink:to="lab_ck0000898745_C000019315Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_MSCIEAFEIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_MSCIEAFEIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MSCI EAFE Index NTR (reflects withholding taxes on foreign dividends, but no deduction for fees, expenses, or other taxes)</link:label>
    <link:label id="lab_ck0000898745_MSCIEAFEIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_MSCIEAFEIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MSCI EAFE Index NTR (reflects withholding taxes on foreign dividends, but no deduction for fees, expenses, or other taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_MSCIEAFEIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_MSCIEAFEIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_MSCIEAFEIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember" xlink:to="lab_ck0000898745_MSCIEAFEIndexNTRreflectswithholdingtaxesonforeigndividendsbutnodeductionforfeesexpensesorothertaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_SPTargetDate2035IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_SPTargetDate2035IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">S&amp;P Target Date 2035 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_SPTargetDate2035IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_SPTargetDate2035IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">S&amp;P Target Date 2035 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_SPTargetDate2035IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_SPTargetDate2035IndexreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_SPTargetDate2035IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0000898745_SPTargetDate2035IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000199325Member_label_en-US" xlink:label="lab_ck0000898745_C000199325Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2050 Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000199325Member_documentation_en-US" xlink:label="lab_ck0000898745_C000199325Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2050 Fund, Class J, C000199325</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000199325Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000199325Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000199325Member" xlink:to="lab_ck0000898745_C000199325Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_SAMStrategicGrowthBlendedIndexexceptasnotedforMSCIEAFEIndexNTRreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_SAMStrategicGrowthBlendedIndexexceptasnotedforMSCIEAFEIndexNTRreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Strategic Growth Blended Index (except as noted for MSCI EAFE Index NTR, reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_SAMStrategicGrowthBlendedIndexexceptasnotedforMSCIEAFEIndexNTRreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_SAMStrategicGrowthBlendedIndexexceptasnotedforMSCIEAFEIndexNTRreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Strategic Growth Blended Index (except as noted for MSCI EAFE Index NTR, reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_SAMStrategicGrowthBlendedIndexexceptasnotedforMSCIEAFEIndexNTRreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_SAMStrategicGrowthBlendedIndexexceptasnotedforMSCIEAFEIndexNTRreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_SAMStrategicGrowthBlendedIndexexceptasnotedforMSCIEAFEIndexNTRreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0000898745_SAMStrategicGrowthBlendedIndexexceptasnotedforMSCIEAFEIndexNTRreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000023512Member_label_en-US" xlink:label="lab_ck0000898745_S000023512Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Overseas Fund</link:label>
    <link:label id="lab_ck0000898745_S000023512Member_documentation_en-US" xlink:label="lab_ck0000898745_S000023512Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Overseas Fund, S000023512</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000023512Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000023512Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000023512Member" xlink:to="lab_ck0000898745_S000023512Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_RussellMidcapValueIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_RussellMidcapValueIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Russell Midcap Value Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_RussellMidcapValueIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_RussellMidcapValueIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Russell Midcap Value Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_RussellMidcapValueIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_RussellMidcapValueIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_RussellMidcapValueIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:to="lab_ck0000898745_RussellMidcapValueIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_MSCIACWIIndexNTRReflectsWithholdingTaxesOnForeignDividendsButNoDeductionForFeesExpensesOrOtherTaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_MSCIACWIIndexNTRReflectsWithholdingTaxesOnForeignDividendsButNoDeductionForFeesExpensesOrOtherTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MSCI ACWI Index NTR (reflects withholding taxes on foreign dividends, but no deduction for fees, expenses, or other taxes)</link:label>
    <link:label id="lab_ck0000898745_MSCIACWIIndexNTRReflectsWithholdingTaxesOnForeignDividendsButNoDeductionForFeesExpensesOrOtherTaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_MSCIACWIIndexNTRReflectsWithholdingTaxesOnForeignDividendsButNoDeductionForFeesExpensesOrOtherTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MSCI ACWI Index NTR (reflects withholding taxes on foreign dividends, but no deduction for fees, expenses, or other taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_MSCIACWIIndexNTRReflectsWithholdingTaxesOnForeignDividendsButNoDeductionForFeesExpensesOrOtherTaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_MSCIACWIIndexNTRReflectsWithholdingTaxesOnForeignDividendsButNoDeductionForFeesExpensesOrOtherTaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_MSCIACWIIndexNTRReflectsWithholdingTaxesOnForeignDividendsButNoDeductionForFeesExpensesOrOtherTaxesIndexMember" xlink:to="lab_ck0000898745_MSCIACWIIndexNTRReflectsWithholdingTaxesOnForeignDividendsButNoDeductionForFeesExpensesOrOtherTaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_SAMFlexibleIncomeBlendedIndexexceptasnotedforMSCIEAFEIndexNTRreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_SAMFlexibleIncomeBlendedIndexexceptasnotedforMSCIEAFEIndexNTRreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Flexible Income Blended Index (except as noted for MSCI EAFE Index NTR, reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_SAMFlexibleIncomeBlendedIndexexceptasnotedforMSCIEAFEIndexNTRreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_SAMFlexibleIncomeBlendedIndexexceptasnotedforMSCIEAFEIndexNTRreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Flexible Income Blended Index (except as noted for MSCI EAFE Index NTR, reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_SAMFlexibleIncomeBlendedIndexexceptasnotedforMSCIEAFEIndexNTRreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_SAMFlexibleIncomeBlendedIndexexceptasnotedforMSCIEAFEIndexNTRreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_SAMFlexibleIncomeBlendedIndexexceptasnotedforMSCIEAFEIndexNTRreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0000898745_SAMFlexibleIncomeBlendedIndexexceptasnotedforMSCIEAFEIndexNTRreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000193004Member_label_en-US" xlink:label="lab_ck0000898745_C000193004Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2065, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000193004Member_documentation_en-US" xlink:label="lab_ck0000898745_C000193004Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2065, Class R-3, C000193004</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000193004Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000193004Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000193004Member" xlink:to="lab_ck0000898745_C000193004Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000063445Member_label_en-US" xlink:label="lab_ck0000898745_C000063445Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2045 Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000063445Member_documentation_en-US" xlink:label="lab_ck0000898745_C000063445Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2045 Fund, Institutional Class, C000063445, LTRIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000063445Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000063445Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000063445Member" xlink:to="lab_ck0000898745_C000063445Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_SandPTargetDateRetirementIncomeIndexreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_SandPTargetDateRetirementIncomeIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">S&amp;P Target Date Retirement Income Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_SandPTargetDateRetirementIncomeIndexreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_SandPTargetDateRetirementIncomeIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">S&amp;P Target Date Retirement Income Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_SandPTargetDateRetirementIncomeIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_SandPTargetDateRetirementIncomeIndexreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_SandPTargetDateRetirementIncomeIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0000898745_SandPTargetDateRetirementIncomeIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019745Member_label_en-US" xlink:label="lab_ck0000898745_C000019745Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2020 Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000019745Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019745Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2020 Fund, Institutional Class, C000019745, PLWIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019745Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019745Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019745Member" xlink:to="lab_ck0000898745_C000019745Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038734Member_label_en-US" xlink:label="lab_ck0000898745_C000038734Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Tax-Exempt Bond Fund, Class A</link:label>
    <link:label id="lab_ck0000898745_C000038734Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038734Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Tax-Exempt Bond Fund, Class A, C000038734, PTEAX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038734Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038734Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038734Member" xlink:to="lab_ck0000898745_C000038734Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019760Member_label_en-US" xlink:label="lab_ck0000898745_C000019760Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2040 Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000019760Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019760Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2040 Fund, Class R-3, C000019760, PTDMX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019760Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019760Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019760Member" xlink:to="lab_ck0000898745_C000019760Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038721Member_label_en-US" xlink:label="lab_ck0000898745_C000038721Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Conservative Balanced Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000038721Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038721Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Conservative Balanced Fund, Institutional Class, C000038721, PCCIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038721Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038721Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038721Member" xlink:to="lab_ck0000898745_C000038721Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000199326Member_label_en-US" xlink:label="lab_ck0000898745_C000199326Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2065 Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000199326Member_documentation_en-US" xlink:label="lab_ck0000898745_C000199326Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2065 Fund, Class J, C000199326</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000199326Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000199326Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000199326Member" xlink:to="lab_ck0000898745_C000199326Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038728Member_label_en-US" xlink:label="lab_ck0000898745_C000038728Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Flexible Income Fund, Class C</link:label>
    <link:label id="lab_ck0000898745_C000038728Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038728Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Flexible Income Fund, Class C, C000038728, SCUPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038728Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038728Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038728Member" xlink:to="lab_ck0000898745_C000038728Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019362Member_label_en-US" xlink:label="lab_ck0000898745_C000019362Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Money Market Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000019362Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019362Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Money Market Fund, Class J, C000019362, PMJXX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019362Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019362Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019362Member" xlink:to="lab_ck0000898745_C000019362Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_SandP500IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_SandP500IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">S&amp;P 500 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_SandP500IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_SandP500IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">S&amp;P 500 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_SandP500IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_SandP500IndexreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_SandP500IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0000898745_SandP500IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_IndexPassiveStrategyRiskMember_label_en-US" xlink:label="lab_ck0000898745_IndexPassiveStrategyRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Index (Passive) Strategy Risk Member</link:label>
    <link:label id="lab_ck0000898745_IndexPassiveStrategyRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_IndexPassiveStrategyRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Index (Passive) Strategy Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_IndexPassiveStrategyRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_IndexPassiveStrategyRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_IndexPassiveStrategyRiskMember" xlink:to="lab_ck0000898745_IndexPassiveStrategyRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038768Member_label_en-US" xlink:label="lab_ck0000898745_C000038768Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Balanced Fund, Class A</link:label>
    <link:label id="lab_ck0000898745_C000038768Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038768Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Balanced Fund, Class A, C000038768, SABPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038768Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038768Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038768Member" xlink:to="lab_ck0000898745_C000038768Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019809Member_label_en-US" xlink:label="lab_ck0000898745_C000019809Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SmallCap Fund, Class A</link:label>
    <link:label id="lab_ck0000898745_C000019809Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019809Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SmallCap Fund, Class A, C000019809, PLLAX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019809Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019809Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019809Member" xlink:to="lab_ck0000898745_C000019809Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000113845Member_label_en-US" xlink:label="lab_ck0000898745_C000113845Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Government &amp; High Quality Bond Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000113845Member_documentation_en-US" xlink:label="lab_ck0000898745_C000113845Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Government &amp; High Quality Bond Fund, Class J, C000113845, PMRJX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000113845Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000113845Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000113845Member" xlink:to="lab_ck0000898745_C000113845Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_EmergingMarketsRiskDefensiveStrategyRiskMember_label_en-US" xlink:label="lab_ck0000898745_EmergingMarketsRiskDefensiveStrategyRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Emerging Markets Risk, Defensive Strategy Risk Member</link:label>
    <link:label id="lab_ck0000898745_EmergingMarketsRiskDefensiveStrategyRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_EmergingMarketsRiskDefensiveStrategyRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Emerging Markets Risk, Defensive Strategy Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_EmergingMarketsRiskDefensiveStrategyRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_EmergingMarketsRiskDefensiveStrategyRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_EmergingMarketsRiskDefensiveStrategyRiskMember" xlink:to="lab_ck0000898745_EmergingMarketsRiskDefensiveStrategyRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019746Member_label_en-US" xlink:label="lab_ck0000898745_C000019746Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2020 Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000019746Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019746Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2020 Fund, Class J, C000019746, PLFJX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019746Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019746Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019746Member" xlink:to="lab_ck0000898745_C000019746Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000145326Member_label_en-US" xlink:label="lab_ck0000898745_C000145326Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2040 Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000145326Member_documentation_en-US" xlink:label="lab_ck0000898745_C000145326Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2040 Fund, Institutional Class, C000145326, PLTQX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000145326Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000145326Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000145326Member" xlink:to="lab_ck0000898745_C000145326Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000210673Member_label_en-US" xlink:label="lab_ck0000898745_C000210673Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Diversified International Fund, Class R-6</link:label>
    <link:label id="lab_ck0000898745_C000210673Member_documentation_en-US" xlink:label="lab_ck0000898745_C000210673Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Diversified International Fund, Class R-6, C000210673</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000210673Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000210673Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000210673Member" xlink:to="lab_ck0000898745_C000210673Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000046562Member_label_en-US" xlink:label="lab_ck0000898745_S000046562Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2045 Fund</link:label>
    <link:label id="lab_ck0000898745_S000046562Member_documentation_en-US" xlink:label="lab_ck0000898745_S000046562Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2045 Fund, S000046562</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000046562Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000046562Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000046562Member" xlink:to="lab_ck0000898745_S000046562Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_DerivativesRiskFuturesRiskMember_label_en-US" xlink:label="lab_ck0000898745_DerivativesRiskFuturesRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Derivatives Risk, Futures Risk Member</link:label>
    <link:label id="lab_ck0000898745_DerivativesRiskFuturesRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_DerivativesRiskFuturesRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Derivatives Risk, Futures Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_DerivativesRiskFuturesRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_DerivativesRiskFuturesRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_DerivativesRiskFuturesRiskMember" xlink:to="lab_ck0000898745_DerivativesRiskFuturesRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000204702Member_label_en-US" xlink:label="lab_ck0000898745_C000204702Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equity Income Fund, Class J</link:label>
    <link:label id="lab_ck0000898745_C000204702Member_documentation_en-US" xlink:label="lab_ck0000898745_C000204702Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Equity Income Fund, Class J</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000204702Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000204702Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000204702Member" xlink:to="lab_ck0000898745_C000204702Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000046555Member_label_en-US" xlink:label="lab_ck0000898745_S000046555Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2060 Fund</link:label>
    <link:label id="lab_ck0000898745_S000046555Member_documentation_en-US" xlink:label="lab_ck0000898745_S000046555Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2060 Fund, S000046555</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000046555Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000046555Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000046555Member" xlink:to="lab_ck0000898745_S000046555Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038781Member_label_en-US" xlink:label="lab_ck0000898745_C000038781Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MidCap Fund, Class C</link:label>
    <link:label id="lab_ck0000898745_C000038781Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038781Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MidCap Fund, Class C, C000038781, PMBCX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038781Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038781Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038781Member" xlink:to="lab_ck0000898745_C000038781Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000149257Member_label_en-US" xlink:label="lab_ck0000898745_C000149257Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">LargeCap Growth Fund I, Class R-6</link:label>
    <link:label id="lab_ck0000898745_C000149257Member_documentation_en-US" xlink:label="lab_ck0000898745_C000149257Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">LargeCap Growth Fund I, Class R-6 Shares, C000149257, PLCGX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000149257Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000149257Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000149257Member" xlink:to="lab_ck0000898745_C000149257Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000054330Member_label_en-US" xlink:label="lab_ck0000898745_S000054330Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finisterre Emerging Markets Total Return Bond Fund</link:label>
    <link:label id="lab_ck0000898745_S000054330Member_documentation_en-US" xlink:label="lab_ck0000898745_S000054330Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Finisterre Emerging Markets Total Return Bond Fund, S000054330</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000054330Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000054330Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000054330Member" xlink:to="lab_ck0000898745_S000054330Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019807Member_label_en-US" xlink:label="lab_ck0000898745_C000019807Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SmallCap Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000019807Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019807Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SmallCap Fund, Institutional Class, C000019807, PSLIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019807Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019807Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019807Member" xlink:to="lab_ck0000898745_C000019807Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_SPTargetDate2060IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_SPTargetDate2060IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">S&amp;P Target Date 2060 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_SPTargetDate2060IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_SPTargetDate2060IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">S&amp;P Target Date 2060 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_SPTargetDate2060IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_SPTargetDate2060IndexreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_SPTargetDate2060IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0000898745_SPTargetDate2060IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019144Member_label_en-US" xlink:label="lab_ck0000898745_C000019144Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Global Emerging Markets Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000019144Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019144Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Global Emerging Markets Fund, Institutional Class, C000019144, PIEIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019144Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019144Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019144Member" xlink:to="lab_ck0000898745_C000019144Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000149262Member_label_en-US" xlink:label="lab_ck0000898745_C000149262Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Global Real Estate Securities Fund, Class R-6</link:label>
    <link:label id="lab_ck0000898745_C000149262Member_documentation_en-US" xlink:label="lab_ck0000898745_C000149262Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Global Real Estate Securities Fund, Class R-6 Shares, C000149262, PGRSX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000149262Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000149262Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000149262Member" xlink:to="lab_ck0000898745_C000149262Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_SandPTargetDate2015IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_SandPTargetDate2015IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">S&amp;P Target Date 2015 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_SandPTargetDate2015IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_SandPTargetDate2015IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">S&amp;P Target Date 2015 Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_SandPTargetDate2015IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_SandPTargetDate2015IndexreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_SandPTargetDate2015IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0000898745_SandPTargetDate2015IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000063449Member_label_en-US" xlink:label="lab_ck0000898745_C000063449Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2055 Fund, Class R-5</link:label>
    <link:label id="lab_ck0000898745_C000063449Member_documentation_en-US" xlink:label="lab_ck0000898745_C000063449Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2055 Fund, Class R-5, C000063449, LTFPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000063449Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000063449Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000063449Member" xlink:to="lab_ck0000898745_C000063449Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038726Member_label_en-US" xlink:label="lab_ck0000898745_C000038726Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Flexible Income Fund, Class A</link:label>
    <link:label id="lab_ck0000898745_C000038726Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038726Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Flexible Income Fund, Class A, C000038726, SAUPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038726Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038726Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038726Member" xlink:to="lab_ck0000898745_C000038726Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000007079Member_label_en-US" xlink:label="lab_ck0000898745_S000007079Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MidCap S&amp;P 400 Index Fund</link:label>
    <link:label id="lab_ck0000898745_S000007079Member_documentation_en-US" xlink:label="lab_ck0000898745_S000007079Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MidCap S&amp;P 400 Index Fund, S000007079</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000007079Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000007079Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000007079Member" xlink:to="lab_ck0000898745_S000007079Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000241176Member_label_en-US" xlink:label="lab_ck0000898745_C000241176Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2070 Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000241176Member_documentation_en-US" xlink:label="lab_ck0000898745_C000241176Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Series S000079799 Principal LifeTime 2070 Fund Class/Contract C000241176 Institutional Class PLTGX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000241176Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000241176Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000241176Member" xlink:to="lab_ck0000898745_C000241176Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019363Member_label_en-US" xlink:label="lab_ck0000898745_C000019363Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Money Market Fund, Class A</link:label>
    <link:label id="lab_ck0000898745_C000019363Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019363Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Money Market Fund, Class A, C000019363, PCSXX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019363Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019363Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019363Member" xlink:to="lab_ck0000898745_C000019363Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019751Member_label_en-US" xlink:label="lab_ck0000898745_C000019751Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2030 Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000019751Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019751Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2030 Fund, Class R-3, C000019751, PTCMX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019751Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019751Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019751Member" xlink:to="lab_ck0000898745_C000019751Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_SovereignDebtRiskMember_label_en-US" xlink:label="lab_ck0000898745_SovereignDebtRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sovereign Debt Risk Member</link:label>
    <link:label id="lab_ck0000898745_SovereignDebtRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_SovereignDebtRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Sovereign Debt Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_SovereignDebtRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_SovereignDebtRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_SovereignDebtRiskMember" xlink:to="lab_ck0000898745_SovereignDebtRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019804Member_label_en-US" xlink:label="lab_ck0000898745_C000019804Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SmallCap Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000019804Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019804Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SmallCap Fund, Class R-3, C000019804, PSBMX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019804Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019804Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019804Member" xlink:to="lab_ck0000898745_C000019804Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000241173Member_label_en-US" xlink:label="lab_ck0000898745_C000241173Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2070 Fund Class R-6</link:label>
    <link:label id="lab_ck0000898745_C000241173Member_documentation_en-US" xlink:label="lab_ck0000898745_C000241173Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2070 Fund Class R-6 , C000241173</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000241173Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000241173Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000241173Member" xlink:to="lab_ck0000898745_C000241173Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_RealEstateInvestmentTrustsREITsRiskMember_label_en-US" xlink:label="lab_ck0000898745_RealEstateInvestmentTrustsREITsRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Real Estate Investment Trusts ("REITs") Risk Member</link:label>
    <link:label id="lab_ck0000898745_RealEstateInvestmentTrustsREITsRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_RealEstateInvestmentTrustsREITsRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Real Estate Investment Trusts ("REITs") Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_RealEstateInvestmentTrustsREITsRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_RealEstateInvestmentTrustsREITsRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_RealEstateInvestmentTrustsREITsRiskMember" xlink:to="lab_ck0000898745_RealEstateInvestmentTrustsREITsRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000149261Member_label_en-US" xlink:label="lab_ck0000898745_C000149261Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Core Fixed Income Fund, Class R-6</link:label>
    <link:label id="lab_ck0000898745_C000149261Member_documentation_en-US" xlink:label="lab_ck0000898745_C000149261Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Core Fixed Income Fund, Class R-6 Shares, C000149261, Class R-6 Shares</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000149261Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000149261Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000149261Member" xlink:to="lab_ck0000898745_C000149261Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000193007Member_label_en-US" xlink:label="lab_ck0000898745_C000193007Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2065, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000193007Member_documentation_en-US" xlink:label="lab_ck0000898745_C000193007Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2065, Institutional Class, C000193007</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000193007Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000193007Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000193007Member" xlink:to="lab_ck0000898745_C000193007Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000210675Member_label_en-US" xlink:label="lab_ck0000898745_C000210675Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MidCap Value Fund I , Class R-6</link:label>
    <link:label id="lab_ck0000898745_C000210675Member_documentation_en-US" xlink:label="lab_ck0000898745_C000210675Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MidCap Value Fund I, Class R-6, C000210675, PCMSX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000210675Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000210675Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000210675Member" xlink:to="lab_ck0000898745_C000210675Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_EquitySecuritiesRiskSmallerCompaniesRiskMember_label_en-US" xlink:label="lab_ck0000898745_EquitySecuritiesRiskSmallerCompaniesRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equity Securities Risk, Smaller Companies Risk Member</link:label>
    <link:label id="lab_ck0000898745_EquitySecuritiesRiskSmallerCompaniesRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_EquitySecuritiesRiskSmallerCompaniesRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Equity Securities Risk, Smaller Companies Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_EquitySecuritiesRiskSmallerCompaniesRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_EquitySecuritiesRiskSmallerCompaniesRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_EquitySecuritiesRiskSmallerCompaniesRiskMember" xlink:to="lab_ck0000898745_EquitySecuritiesRiskSmallerCompaniesRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000046557Member_label_en-US" xlink:label="lab_ck0000898745_S000046557Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2020 Fund</link:label>
    <link:label id="lab_ck0000898745_S000046557Member_documentation_en-US" xlink:label="lab_ck0000898745_S000046557Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2020 Fund, S000046557</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000046557Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000046557Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000046557Member" xlink:to="lab_ck0000898745_S000046557Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000038724Member_label_en-US" xlink:label="lab_ck0000898745_C000038724Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SAM Conservative Growth Fund, Class C</link:label>
    <link:label id="lab_ck0000898745_C000038724Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038724Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Conservative Growth Fund, Class C, C000038724, SCGPX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000038724Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000038724Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000038724Member" xlink:to="lab_ck0000898745_C000038724Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019086Member_label_en-US" xlink:label="lab_ck0000898745_C000019086Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inflation Protection Fund, Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000019086Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019086Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Inflation Protection Fund, Institutional Class, C000019086 PIPIX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019086Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019086Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019086Member" xlink:to="lab_ck0000898745_C000019086Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_GeographicConcentrationRisk1Member_label_en-US" xlink:label="lab_ck0000898745_GeographicConcentrationRisk1Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Geographic Concentration Risk1 Member</link:label>
    <link:label id="lab_ck0000898745_GeographicConcentrationRisk1Member_documentation_en-US" xlink:label="lab_ck0000898745_GeographicConcentrationRisk1Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Geographic Concentration Risk1 Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_GeographicConcentrationRisk1Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_GeographicConcentrationRisk1Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_GeographicConcentrationRisk1Member" xlink:to="lab_ck0000898745_GeographicConcentrationRisk1Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_TargetDateFundRiskMember_label_en-US" xlink:label="lab_ck0000898745_TargetDateFundRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Target Date Fund Risk Member</link:label>
    <link:label id="lab_ck0000898745_TargetDateFundRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_TargetDateFundRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Target Date Fund Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_TargetDateFundRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_TargetDateFundRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_TargetDateFundRiskMember" xlink:to="lab_ck0000898745_TargetDateFundRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_DerivativesRiskMember_label_en-US" xlink:label="lab_ck0000898745_DerivativesRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Derivatives Risk Member</link:label>
    <link:label id="lab_ck0000898745_DerivativesRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_DerivativesRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Derivatives Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_DerivativesRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_DerivativesRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_DerivativesRiskMember" xlink:to="lab_ck0000898745_DerivativesRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000210674Member_label_en-US" xlink:label="lab_ck0000898745_C000210674Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MidCap Value Fund I, Class A</link:label>
    <link:label id="lab_ck0000898745_C000210674Member_documentation_en-US" xlink:label="lab_ck0000898745_C000210674Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MidCap Value Fund I, Class A, C000210674, PCMVX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000210674Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000210674Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000210674Member" xlink:to="lab_ck0000898745_C000210674Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_S000046558Member_label_en-US" xlink:label="lab_ck0000898745_S000046558Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2025 Fund</link:label>
    <link:label id="lab_ck0000898745_S000046558Member_documentation_en-US" xlink:label="lab_ck0000898745_S000046558Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2025 Fund, S000046558</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_S000046558Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_S000046558Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_S000046558Member" xlink:to="lab_ck0000898745_S000046558Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019585Member_label_en-US" xlink:label="lab_ck0000898745_C000019585Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SmallCap Value II Fund, Class R-3</link:label>
    <link:label id="lab_ck0000898745_C000019585Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019585Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SmallCap Value II Fund, Class R-3, C000019585, PJARX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019585Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019585Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019585Member" xlink:to="lab_ck0000898745_C000019585Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000019747Member_label_en-US" xlink:label="lab_ck0000898745_C000019747Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2020 Fund, Class A</link:label>
    <link:label id="lab_ck0000898745_C000019747Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019747Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime 2020 Fund, Class A, C000019747, PTBAX</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000019747Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000019747Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000019747Member" xlink:to="lab_ck0000898745_C000019747Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_BankLoansRiskMember_label_en-US" xlink:label="lab_ck0000898745_BankLoansRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Bank Loans Risk Member</link:label>
    <link:label id="lab_ck0000898745_BankLoansRiskMember_documentation_en-US" xlink:label="lab_ck0000898745_BankLoansRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Bank Loans Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_BankLoansRiskMember" xlink:href="ck0000898745-20260227.xsd#ck0000898745_BankLoansRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_BankLoansRiskMember" xlink:to="lab_ck0000898745_BankLoansRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_C000241174Member_label_en-US" xlink:label="lab_ck0000898745_C000241174Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2070 Fund Institutional Class</link:label>
    <link:label id="lab_ck0000898745_C000241174Member_documentation_en-US" xlink:label="lab_ck0000898745_C000241174Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2070 Fund Institutional Class , C000241174</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0000898745_C000241174Member" xlink:href="ck0000898745-20260227.xsd#ck0000898745_C000241174Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0000898745_C000241174Member" xlink:to="lab_ck0000898745_C000241174Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0000898745_SPTargetDate2065IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0000898745_SPTargetDate2065IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">S&amp;P Target Date 2065+ Index (reflects no deduction for fees, expenses, or taxes)</link:label>
    <link:label id="lab_ck0000898745_SPTargetDate2065IndexreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0000898745_SPTargetDate2065IndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">S&amp;P Target Date 2065+ Index (reflects no deduction for fees, expenses, or taxes)</link:label>
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    <link:label id="lab_ck0000898745_C000241180Member_documentation_en-US" xlink:label="lab_ck0000898745_C000241180Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Series S000079799 Principal LifeTime 2070 Fund Class/Contract C000241180 Class J PLTLX</link:label>
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    <link:label id="lab_ck0000898745_C000149260Member_documentation_en-US" xlink:label="lab_ck0000898745_C000149260Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SmallCap Growth Fund I, Class R-6 Shares, C000149260, PCSMX</link:label>
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    <link:label id="lab_ck0000898745_C000038725Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038725Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Conservative Growth Fund, Institutional Class, C000038725, PCWIX</link:label>
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    <link:label id="lab_ck0000898745_C000145329Member_documentation_en-US" xlink:label="lab_ck0000898745_C000145329Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2045 Fund, Institutional Class, C000145329, PHTYX</link:label>
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    <link:label id="lab_ck0000898745_C000019145Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019145Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Global Emerging Markets Fund, Class J, C000019145, PIEJX</link:label>
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    <link:label id="lab_ck0000898745_S000007083Member_documentation_en-US" xlink:label="lab_ck0000898745_S000007083Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">International Fund , S000007083</link:label>
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    <link:label id="lab_ck0000898745_C000038730Member_documentation_en-US" xlink:label="lab_ck0000898745_C000038730Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">SAM Strategic Growth Fund, Class A, C000038730, SACAX</link:label>
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    <link:label id="lab_ck0000898745_C000193008Member_documentation_en-US" xlink:label="lab_ck0000898745_C000193008Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal LifeTime Hybrid 2065, Class R-6, C000193008</link:label>
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    <link:label id="lab_ck0000898745_C000019313Member_documentation_en-US" xlink:label="lab_ck0000898745_C000019313Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MidCap Fund, Class R-5, C000019313, PMBPX</link:label>
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