<?xml version="1.0"?>
<ownershipDocument>
    <schemaVersion>X0201</schemaVersion>

    <documentType>3</documentType><periodOfReport>2004-01-12</periodOfReport>
    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0000030554</issuerCik>
        <issuerName>DUPONT E I DE NEMOURS &amp; CO</issuerName>
        <issuerTradingSymbol>DD</issuerTradingSymbol></issuer><reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001275972</rptOwnerCik>
            <rptOwnerName>BOREL JAMES C</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1007 MARKET STREET</rptOwnerStreet1>
            <rptOwnerStreet2>D-9000</rptOwnerStreet2>
            <rptOwnerCity>WILMINGTON</rptOwnerCity>
            <rptOwnerState>DE</rptOwnerState>
            <rptOwnerZipCode>19898</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
            <reportingOwnerRelationship>
<isDirector>0</isDirector><isOfficer>1</isOfficer><isTenPercentOwner>0</isTenPercentOwner><isOther>0</isOther><officerTitle>Senior Vice President</officerTitle></reportingOwnerRelationship></reportingOwner><nonDerivativeTable><nonDerivativeHolding><securityTitle><value>Common Stock</value></securityTitle><postTransactionAmounts><sharesOwnedFollowingTransaction><value>2228</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value/></natureOfOwnership></ownershipNature></nonDerivativeHolding><nonDerivativeHolding><securityTitle><value>Common Stock</value></securityTitle><postTransactionAmounts><sharesOwnedFollowingTransaction><value>4878.3479</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>I</value></directOrIndirectOwnership><natureOfOwnership><value>DuPont SIP Trust</value></natureOfOwnership></ownershipNature></nonDerivativeHolding><nonDerivativeHolding><securityTitle><value>Common Stock</value></securityTitle><postTransactionAmounts><sharesOwnedFollowingTransaction><value>447.1625</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>I</value></directOrIndirectOwnership><natureOfOwnership><value>Salary Deferral &amp; Savings Restoration Plan</value></natureOfOwnership></ownershipNature></nonDerivativeHolding><nonDerivativeHolding><securityTitle><value>Common Stock</value></securityTitle><postTransactionAmounts><sharesOwnedFollowingTransaction><value>60</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>I</value></directOrIndirectOwnership><natureOfOwnership><value>Custodial accounts for children.</value></natureOfOwnership></ownershipNature></nonDerivativeHolding></nonDerivativeTable><derivativeTable><derivativeHolding><securityTitle><value>Employee Stock Options (Right to Buy)) NQOs and ISOs</value></securityTitle><conversionOrExercisePrice><value>37.75</value></conversionOrExercisePrice><exerciseDate><value>2004-02-05</value><footnoteId id="F1"/></exerciseDate><expirationDate><value>2013-02-04</value></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Common Stock</value></underlyingSecurityTitle><underlyingSecurityShares><value>27300</value></underlyingSecurityShares></underlyingSecurity><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value/></natureOfOwnership></ownershipNature></derivativeHolding><derivativeHolding><securityTitle><value>Employee Stock Options (Right to Buy) NQOs and ISOs</value></securityTitle><conversionOrExercisePrice><value>42.50</value></conversionOrExercisePrice><exerciseDate><value>2003-02-06</value><footnoteId id="F1"/></exerciseDate><expirationDate><value>2012-02-05</value></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Common Stock</value></underlyingSecurityTitle><underlyingSecurityShares><value>27300</value></underlyingSecurityShares></underlyingSecurity><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value/></natureOfOwnership></ownershipNature></derivativeHolding><derivativeHolding><securityTitle><value>Employee Stock Options (Right to Buy) NQOs</value></securityTitle><conversionOrExercisePrice><value>44.50</value></conversionOrExercisePrice><exerciseDate><value>2003-01-08</value><footnoteId id="F2"/></exerciseDate><expirationDate><value>2012-01-07</value></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Common Stock</value></underlyingSecurityTitle><underlyingSecurityShares><value>200</value></underlyingSecurityShares></underlyingSecurity><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value/></natureOfOwnership></ownershipNature></derivativeHolding><derivativeHolding><securityTitle><value>Employee Stock Options (Right to Buy) NQOs and ISOs</value></securityTitle><conversionOrExercisePrice><value>43.25</value></conversionOrExercisePrice><exerciseDate><value>2002-02-07</value><footnoteId id="F1"/></exerciseDate><expirationDate><value>2011-02-06</value></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Common Stock</value></underlyingSecurityTitle><underlyingSecurityShares><value>31800</value></underlyingSecurityShares></underlyingSecurity><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value/></natureOfOwnership></ownershipNature></derivativeHolding><derivativeHolding><securityTitle><value>Employee Stock Options (Right to Buy) NQOs and ISOs</value></securityTitle><conversionOrExercisePrice><value>61.00</value></conversionOrExercisePrice><exerciseDate><value>2001-02-02</value><footnoteId id="F1"/></exerciseDate><expirationDate><value>2010-02-01</value></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Common Stock</value></underlyingSecurityTitle><underlyingSecurityShares><value>17200</value></underlyingSecurityShares></underlyingSecurity><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value/></natureOfOwnership></ownershipNature></derivativeHolding><derivativeHolding><securityTitle><value>Employee Stock Options (Right to Buy) NQOs and ISOs</value></securityTitle><conversionOrExercisePrice><value>52.50</value></conversionOrExercisePrice><exerciseDate><value>2000-02-03</value><footnoteId id="F1"/></exerciseDate><expirationDate><value>2009-02-02</value></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Common Stock</value></underlyingSecurityTitle><underlyingSecurityShares><value>16200</value></underlyingSecurityShares></underlyingSecurity><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value/></natureOfOwnership></ownershipNature></derivativeHolding><derivativeHolding><securityTitle><value>Employee Stock Options (Right to Buy) NQOs and ISOs</value></securityTitle><conversionOrExercisePrice><value>59.50</value></conversionOrExercisePrice><exerciseDate><value>1999-02-04</value><footnoteId id="F1"/></exerciseDate><expirationDate><value>2008-02-03</value></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Common Stock</value></underlyingSecurityTitle><underlyingSecurityShares><value>10600</value></underlyingSecurityShares></underlyingSecurity><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value/></natureOfOwnership></ownershipNature></derivativeHolding><derivativeHolding><securityTitle><value>Employee Stock Options (Right to Buy) NQOs</value></securityTitle><conversionOrExercisePrice><value>52.50</value></conversionOrExercisePrice><exerciseDate><value>1998-01-29</value><footnoteId id="F2"/></exerciseDate><expirationDate><value>2007-01-28</value></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Common Stock</value></underlyingSecurityTitle><underlyingSecurityShares><value>200</value></underlyingSecurityShares></underlyingSecurity><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value/></natureOfOwnership></ownershipNature></derivativeHolding><derivativeHolding><securityTitle><value>Employee Stock Options (Right to Buy) NQOs and ISOs</value></securityTitle><conversionOrExercisePrice><value>52.50</value></conversionOrExercisePrice><exerciseDate><value>1998-01-29</value><footnoteId id="F3"/></exerciseDate><expirationDate><value>2007-01-28</value></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Common Stock</value></underlyingSecurityTitle><underlyingSecurityShares><value>8160</value></underlyingSecurityShares></underlyingSecurity><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value/></natureOfOwnership></ownershipNature></derivativeHolding><derivativeHolding><securityTitle><value>Employee Stock Options (Right to Buy) NQOs and ISOs</value></securityTitle><conversionOrExercisePrice><value>39.625</value></conversionOrExercisePrice><exerciseDate><value>1997-02-07</value><footnoteId id="F3"/></exerciseDate><expirationDate><value>2006-02-06</value></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Common Stock</value></underlyingSecurityTitle><underlyingSecurityShares><value>6770</value></underlyingSecurityShares></underlyingSecurity><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value/></natureOfOwnership></ownershipNature></derivativeHolding><derivativeHolding><securityTitle><value>Employee Stock Options (Right to Buy) NQOs and ISOs</value></securityTitle><conversionOrExercisePrice><value>27.75</value></conversionOrExercisePrice><exerciseDate><value>1996-03-03</value><footnoteId id="F3"/></exerciseDate><expirationDate><value>2005-03-02</value></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Common Stock</value></underlyingSecurityTitle><underlyingSecurityShares><value>7200</value></underlyingSecurityShares></underlyingSecurity><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value/></natureOfOwnership></ownershipNature></derivativeHolding><derivativeHolding><securityTitle><value>Employee Stock Options (Right to Buy) NQOs</value></securityTitle><conversionOrExercisePrice><value>28.50</value></conversionOrExercisePrice><exerciseDate><value>1996-01-25</value><footnoteId id="F2"/></exerciseDate><expirationDate><value>2005-01-24</value></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Common Stock</value></underlyingSecurityTitle><underlyingSecurityShares><value>200</value></underlyingSecurityShares></underlyingSecurity><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value/></natureOfOwnership></ownershipNature></derivativeHolding><derivativeHolding><securityTitle><value>DuPont Common Stock Units</value><footnoteId id="F4"/></securityTitle><conversionOrExercisePrice><value>0</value></conversionOrExercisePrice><exerciseDate><footnoteId id="F5"/></exerciseDate><expirationDate><footnoteId id="F6"/></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Common Stock</value></underlyingSecurityTitle><underlyingSecurityShares><value>4974.0967</value></underlyingSecurityShares></underlyingSecurity><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value/></natureOfOwnership></ownershipNature></derivativeHolding></derivativeTable><footnotes><footnote id="F1">Options become exercisable in three equal annual installments beginning on the first anniversary of the grant, provided the 120% stock price hurdle is met; option shares may be used to satisfy withholding taxes.</footnote><footnote id="F2">Options become exercisable one year from date of grant.</footnote><footnote id="F3">Options become exercisable one year from date of grant only if price hurdle is met; option shares may be used to satisfy withholding taxes.</footnote><footnote id="F4">Deferred units under the DuPont Variable Compensation Plan.</footnote><footnote id="F5">Units convert one-for-one to DuPont common stock.</footnote><footnote id="F6">Units become payable in common stock at the election of the reporting person.</footnote></footnotes><remarks/><ownerSignature><signatureName>James C. Borel by Mary E. Bowler</signatureName><signatureDate>2004-01-22</signatureDate></ownerSignature></ownershipDocument>

