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          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>State Street SPDR Dow Jones REIT ETF</name>
        <lei>54930077YVRJPO64VF50</lei>
        <title>State Street SPDR Dow Jones REIT ETF</title>
        <cusip>78464A607</cusip>
        <identifiers>
          <isin value="US78464A6073"/>
        </identifiers>
        <balance>20642.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>2331926.74000000</valUSD>
        <pctVal>2.407951275742</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerConditional desc="REIT" issuerCat="OTHER"/>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>State Street SPDR Portfolio S&amp;P 400 Mid Cap ETF</name>
        <lei>549300TKUU0ZLRVSLJ96</lei>
        <title>State Street SPDR Portfolio S&amp;P 400 Mid Cap ETF</title>
        <cusip>78464A847</cusip>
        <identifiers>
          <isin value="US78464A8475"/>
        </identifiers>
        <balance>108244.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>7312964.64000000</valUSD>
        <pctVal>7.551378965854</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>RF</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>State Street SPDR Portfolio S&amp;P 600 Small Cap ETF</name>
        <lei>549300NYZX301TBLUJ08</lei>
        <title>State Street SPDR Portfolio S&amp;P 600 Small Cap ETF</title>
        <cusip>78468R853</cusip>
        <identifiers>
          <isin value="US78468R8530"/>
        </identifiers>
        <balance>86925.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>5012964.75000000</valUSD>
        <pctVal>5.176395406408</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>RF</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Schwab U.S. REIT ETF</name>
        <lei>549300OLDKO120DR6467</lei>
        <title>Schwab U.S. REIT ETF</title>
        <cusip>808524847</cusip>
        <identifiers>
          <isin value="US8085248479"/>
        </identifiers>
        <balance>97660.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>2312588.80000000</valUSD>
        <pctVal>2.387982888016</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerConditional desc="REIT" issuerCat="OTHER"/>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>United States Treasury</name>
        <lei>254900HROIFWPRGM1V77</lei>
        <title>U.S. Treasury Bills</title>
        <cusip>912797TQ0</cusip>
        <identifiers>
          <isin value="US912797TQ02"/>
        </identifiers>
        <balance>490000.00000000</balance>
        <units>PA</units>
        <curCd>USD</curCd>
        <valUSD>488580.97000000</valUSD>
        <pctVal>0.504509489871</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>STIV</assetCat>
        <issuerCat>UST</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>2</fairValLevel>
        <debtSec>
          <maturityDt>2026-07-30</maturityDt>
          <couponKind>None</couponKind>
          <annualizedRt>0.00000000</annualizedRt>
          <isDefault>N</isDefault>
          <areIntrstPmntsInArrs>N</areIntrstPmntsInArrs>
          <isPaidKind>N</isPaidKind>
        </debtSec>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>United States Treasury</name>
        <lei>254900HROIFWPRGM1V77</lei>
        <title>U.S. Treasury Notes</title>
        <cusip>91282CLH2</cusip>
        <identifiers>
          <isin value="US91282CLH24"/>
        </identifiers>
        <balance>480000.00000000</balance>
        <units>PA</units>
        <curCd>USD</curCd>
        <valUSD>479934.00000000</valUSD>
        <pctVal>0.495580614840</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>DBT</assetCat>
        <issuerCat>UST</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>2</fairValLevel>
        <debtSec>
          <maturityDt>2026-08-31</maturityDt>
          <couponKind>Fixed</couponKind>
          <annualizedRt>3.75000000</annualizedRt>
          <isDefault>N</isDefault>
          <areIntrstPmntsInArrs>N</areIntrstPmntsInArrs>
          <isPaidKind>N</isPaidKind>
        </debtSec>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Citibank NA</name>
        <lei>E57ODZWZ7FF32TWEFA76</lei>
        <title>Long: 563457    TRS USD R E RCV EQTY / Short: 563457    TRS USD P F   .12000 PAY FIXED</title>
        <cusip>000000000</cusip>
        <identifiers>
          <other otherDesc="Internal Identifier" value="563457"/>
        </identifiers>
        <balance>1447170.27000000</balance>
        <units>OU</units>
        <descOthUnits>Notional Amount</descOthUnits>
        <curCd>USD</curCd>
        <valUSD>-113746.23000000</valUSD>
        <pctVal>-0.11745453874</pctVal>
        <payoffProfile>N/A</payoffProfile>
        <assetCat>DCO</assetCat>
        <issuerConditional desc="derivative" issuerCat="OTHER"/>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>2</fairValLevel>
        <derivativeInfo>
          <swapDeriv derivCat="SWP">
            <counterparties>
              <counterpartyName>Citibank NA</counterpartyName>
              <counterpartyLei>E57ODZWZ7FF32TWEFA76</counterpartyLei>
            </counterparties>
            <descRefInstrmnt>
              <indexBasketInfo>
                <indexName>Bloomberg Commodity Index 3 Month Forward</indexName>
                <indexIdentifier>BCOMF3 Index</indexIdentifier>
              </indexBasketInfo>
            </descRefInstrmnt>
            <swapFlag>Y</swapFlag>
            <otherRecDesc fixedOrFloating="Other">equity-performance leg</otherRecDesc>
            <fixedPmntDesc amount="-4.76000000" curCd="USD" fixedOrFloating="Fixed" fixedRt="0.12000000"/>
            <terminationDt>2026-10-31</terminationDt>
            <upfrontPmnt>0.00000000</upfrontPmnt>
            <pmntCurCd>USD</pmntCurCd>
            <upfrontRcpt>0.00000000</upfrontRcpt>
            <rcptCurCd>USD</rcptCurCd>
            <notionalAmt>1447170.27000000</notionalAmt>
            <curCd>USD</curCd>
            <unrealizedAppr>-113746.23000000</unrealizedAppr>
          </swapDeriv>
        </derivativeInfo>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
    </invstOrSecs>
    <explntrNotes>
      <explntrNote note="Monthly returns presented in Item B.5(a) have been calculated without deducting any applicable sales loads or redemption fees." noteItem="B.5.a"/>
      <explntrNote note="Please see notes to financial statements or N-PORT part F for a glossary of swap paid and received terms." noteItem="C.11.a"/>
    </explntrNotes>
    <signature>
      <ncom:dateSigned>2026-07-15</ncom:dateSigned>
      <ncom:nameOfApplicant>NORTHWESTERN MUTUAL SERIES FUND INC</ncom:nameOfApplicant>
      <ncom:signature>Linda Wisniewski</ncom:signature>
      <ncom:signerName>Linda Wisniewski</ncom:signerName>
      <ncom:title>Controller and Chief Accounting Officer</ncom:title>
    </signature>
  </formData>
</edgarSubmission>
