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        <identifiers>
          <isin value="US6681407911"/>
        </identifiers>
        <balance>6957459.57000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>12078149.81000000</valUSD>
        <pctVal>3.773789067596</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>Northwestern Mutual Series Fund, Inc. - Small Cap Value Portfolio</name>
        <lei>5493006BEZYY47A02J59</lei>
        <title>SMALL CAP VALUE PORTFOLIO</title>
        <cusip>668140817</cusip>
        <identifiers>
          <isin value="US6681408174"/>
        </identifiers>
        <balance>1219232.64000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>2923719.87000000</valUSD>
        <pctVal>0.913509292042</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>Northwestern Mutual Series Fund, Inc. - Small Cap Growth Stock Portfolio</name>
        <lei>YTR2S467AP5XPLF6CQ13</lei>
        <title>SMALL CAP GROWTH STK PORTFOLIO</title>
        <cusip>668140825</cusip>
        <identifiers>
          <isin value="US6681408257"/>
        </identifiers>
        <balance>946429.87000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>3030468.43000000</valUSD>
        <pctVal>0.946862624717</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>Northwestern Mutual Series Fund, Inc. - Mid Cap Growth Stock Portfolio</name>
        <lei>LIP0ME8UWTR611J45283</lei>
        <title>MID CAP GROWTH PORTFOLIO</title>
        <cusip>668140866</cusip>
        <identifiers>
          <isin value="US6681408661"/>
        </identifiers>
        <balance>1731881.04000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>5872808.62000000</valUSD>
        <pctVal>1.834945030065</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>Northwestern Mutual Series Fund, Inc. - Multi-Sector Bond Portfolio</name>
        <lei>P0C14V6IL3O47L1ZG636</lei>
        <title>PIMCO MULTI SECTOR BD PORT MUTUAL FUND</title>
        <cusip>668140882</cusip>
        <identifiers>
          <isin value="US6681408828"/>
        </identifiers>
        <balance>14674890.43000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>15364610.28000000</valUSD>
        <pctVal>4.800635793946</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 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>50260.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>5677872.20000000</valUSD>
        <pctVal>1.774037611110</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 Long Term Treasury ETF</name>
        <lei>549300GYQKAMF6JUVI06</lei>
        <title>State Street SPDR Portfolio Long Term Treasury ETF</title>
        <cusip>78464A664</cusip>
        <identifiers>
          <isin value="US78464A6644"/>
        </identifiers>
        <balance>226110.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>5930865.30000000</valUSD>
        <pctVal>1.853084701101</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 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>230300.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>15559068.00000000</valUSD>
        <pctVal>4.861393644229</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>162948.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>9397211.16000000</valUSD>
        <pctVal>2.936136188022</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>239340.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>5667571.20000000</valUSD>
        <pctVal>1.770819088257</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>2300000.00000000</balance>
        <units>PA</units>
        <curCd>USD</curCd>
        <valUSD>2293339.27000000</valUSD>
        <pctVal>0.716548378812</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>2300000.00000000</balance>
        <units>PA</units>
        <curCd>USD</curCd>
        <valUSD>2299683.75000000</valUSD>
        <pctVal>0.718530696439</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: 563447    TRS USD R E RCV EQTY / Short: 563447    TRS USD P F   .12000 PAY FIXED</title>
        <cusip>000000000</cusip>
        <identifiers>
          <other otherDesc="Internal Identifier" value="563447"/>
        </identifiers>
        <balance>6864782.05000000</balance>
        <units>OU</units>
        <descOthUnits>Notional Amount</descOthUnits>
        <curCd>USD</curCd>
        <valUSD>-539565.45000000</valUSD>
        <pctVal>-0.16858593646</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="-22.57000000" 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>6864782.05000000</notionalAmt>
            <curCd>USD</curCd>
            <unrealizedAppr>-539565.45000000</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>
