-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 N48scVXvegn9iTBklN5VnByV+X5yr+W6ZSmxkDT5aS5tmU3w4kFx2MydR+r5dVaW
 T92wJ7OoJ64mhvbWDi6jGQ==

<SEC-DOCUMENT>0000790070-09-000066.txt : 20090821
<SEC-HEADER>0000790070-09-000066.hdr.sgml : 20090821
<ACCEPTANCE-DATETIME>20090821160729
ACCESSION NUMBER:		0000790070-09-000066
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20090819
FILED AS OF DATE:		20090821
DATE AS OF CHANGE:		20090821

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			HAUCK FRANK
		CENTRAL INDEX KEY:			0001189181

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-09853
		FILM NUMBER:		091028781

	MAIL ADDRESS:	
		STREET 1:		176 SOUTH STREET
		CITY:			HOPKINTON
		STATE:			MA
		ZIP:			01748

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			EMC CORP
		CENTRAL INDEX KEY:			0000790070
		STANDARD INDUSTRIAL CLASSIFICATION:	COMPUTER STORAGE DEVICES [3572]
		IRS NUMBER:				042680009
		STATE OF INCORPORATION:			MA
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		176 SOUTH STREET
		CITY:			HOPKINTON
		STATE:			MA
		ZIP:			01748-9103
		BUSINESS PHONE:		5082937208

	MAIL ADDRESS:	
		STREET 1:		176 SOUTH STREET
		CITY:			HOPKINTON
		STATE:			MA
		ZIP:			01748-9103
</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>2009-08-19</periodOfReport>

    <issuer>
        <issuerCik>0000790070</issuerCik>
        <issuerName>EMC CORP</issuerName>
        <issuerTradingSymbol>EMC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001189181</rptOwnerCik>
            <rptOwnerName>HAUCK FRANK</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>EMC CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>176 SOUTH STREET</rptOwnerStreet2>
            <rptOwnerCity>HOPKINTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>01748</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>EVP, Gbl Mktg &amp; Cust. Quality</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2009-08-19</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>100000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>15.08</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>683767</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2009-08-20</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>5845</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>677922</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Shares withheld by EMC to satisfy certain taxes payable in connection with the vesting of previously awarded restricted stock units.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Jacquelyn A. Connelly, Attorney In Fact</signatureName>
        <signatureDate>2009-08-21</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----