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<!-- DFS ActiveDisclosure(SM) XBRL Schema Document - http://www.dfsco.com/financial-services/ -->
<!-- Creation Date      : 2019-02-27T23:24:29.3445940+00:00 -->
<!-- Version            : 3.3.6989.14284 -->
<!-- Package ID         : d093f5502db54f35bb6f955f9042866b -->
<!-- Copyright (c) 2019 Donnelley Financial, LLC. All Rights Reserved. -->
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  <element id="pkg_HighStockPricePerShare" name="HighStockPricePerShare" type="num:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <element id="pkg_LowStockPricePerShare" name="LowStockPricePerShare" type="num:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <element id="pkg_QuarterlyFinancialDataLineItems" name="QuarterlyFinancialDataLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="pkg_ScheduleOfQuarterlyFinancialDataTable" name="ScheduleOfQuarterlyFinancialDataTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="pkg_PackagingAndCorporateAndOtherMember" name="PackagingAndCorporateAndOtherMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="pkg_RestructuringAndRelatedCostAfterTax" name="RestructuringAndRelatedCostAfterTax" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <element id="pkg_RestructuringAndRelatedCostIncomeLossPerShareDiluted" name="RestructuringAndRelatedCostIncomeLossPerShareDiluted" type="num:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <element id="pkg_IncomeTaxReconciliationFederalTaxReformTaxCutsAndJobsActOf2017Amount" name="IncomeTaxReconciliationFederalTaxReformTaxCutsAndJobsActOf2017Amount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <element id="pkg_ChangeInValueOfDeferredTaxAssetsDueToInternalConsolidation" name="ChangeInValueOfDeferredTaxAssetsDueToInternalConsolidation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
</schema>
