-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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<SEC-DOCUMENT>0001120652-10-000012.txt : 20100803
<SEC-HEADER>0001120652-10-000012.hdr.sgml : 20100803
<ACCEPTANCE-DATETIME>20100803141033
ACCESSION NUMBER:		0001120652-10-000012
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100731
FILED AS OF DATE:		20100803
DATE AS OF CHANGE:		20100803

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BROWN RICHARD H
		CENTRAL INDEX KEY:			0001120652

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-00815
		FILM NUMBER:		10987008

	MAIL ADDRESS:	
		STREET 1:		5400 LEGACY DRIVE
		CITY:			FRISCO
		STATE:			TX
		ZIP:			75024

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			DUPONT E I DE NEMOURS & CO
		CENTRAL INDEX KEY:			0000030554
		STANDARD INDUSTRIAL CLASSIFICATION:	PLASTIC MATERIAL, SYNTH RESIN/RUBBER, CELLULOS (NO GLASS) [2820]
		IRS NUMBER:				510014090
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1007 MARKET ST
		CITY:			WILMINGTON
		STATE:			DE
		ZIP:			19898
		BUSINESS PHONE:		3027741000

	MAIL ADDRESS:	
		STREET 1:		1007 MARKET ST
		CITY:			WILMINGTON
		STATE:			DE
		ZIP:			19898
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-07-31</periodOfReport>

    <issuer>
        <issuerCik>0000030554</issuerCik>
        <issuerName>DUPONT E I DE NEMOURS &amp; CO</issuerName>
        <issuerTradingSymbol>DD</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001120652</rptOwnerCik>
            <rptOwnerName>BROWN RICHARD H</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>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-07-31</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>198.3442</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>40.67</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>33464.4861</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-08-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2340</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>41.632</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>31124.4861</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Includes direct ownership, unvested RSUs and vested deferred stock units.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Mary E. Bowler by Power of Attorney</signatureName>
        <signatureDate>2010-08-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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