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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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 /bs+DGyAA+iXRtkezqZ6HQ==

<SEC-DOCUMENT>0001209191-03-033262.txt : 20031203
<SEC-HEADER>0001209191-03-033262.hdr.sgml : 20031203
<ACCEPTANCE-DATETIME>20031203092843
ACCESSION NUMBER:		0001209191-03-033262
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20031201
FILED AS OF DATE:		20031203

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MERCK & CO INC
		CENTRAL INDEX KEY:			0000064978
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				221109110
		STATE OF INCORPORATION:			NJ
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		ONE MERCK DR
		STREET 2:		P O BOX 100
		CITY:			WHITEHOUSE STATION
		STATE:			NJ
		ZIP:			08889-0100
		BUSINESS PHONE:		9084234044

	MAIL ADDRESS:	
		STREET 1:		ONE MERCK DR
		STREET 2:		PO BOX 100 WS3AB-05
		CITY:			WHITEHOUSE STATION
		STATE:			NJ
		ZIP:			08889-0100

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			LEWENT JUDY C
		CENTRAL INDEX KEY:			0001140890

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-03305
		FILM NUMBER:		031033927

	BUSINESS ADDRESS:	
		STREET 1:		ONE DELL WAY
		CITY:			ROUND ROCK
		STATE:			TX
		ZIP:			786822244
		BUSINESS PHONE:		5127284737

	MAIL ADDRESS:	
		STREET 1:		PO BOX 100
		CITY:			WHITEHOUSE STATION
		STATE:			NJ
		ZIP:			08889
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
<TEXT>
<XML>
<?xml version="1.0"?><ownershipDocument><schemaVersion>X0201</schemaVersion>    <documentType>4</documentType><periodOfReport>2003-12-01</periodOfReport><notSubjectToSection16>0</notSubjectToSection16><issuer><issuerCik>0000064978</issuerCik><issuerName>MERCK &amp; CO INC</issuerName>        <issuerTradingSymbol>(MRK)</issuerTradingSymbol></issuer><reportingOwner><reportingOwnerId><rptOwnerCik>0001140890</rptOwnerCik><rptOwnerName>LEWENT JUDY C</rptOwnerName></reportingOwnerId><reportingOwnerAddress><rptOwnerStreet1>ONE MERCK DRIVE</rptOwnerStreet1><rptOwnerStreet2></rptOwnerStreet2><rptOwnerCity>WHITEHOUSE STATION</rptOwnerCity><rptOwnerState>NJ</rptOwnerState><rptOwnerZipCode>08889-0100</rptOwnerZipCode><rptOwnerStateDescription></rptOwnerStateDescription></reportingOwnerAddress><reportingOwnerRelationship><isDirector>0</isDirector><isOfficer>1</isOfficer><isTenPercentOwner>0</isTenPercentOwner><isOther>0</isOther><officerTitle>Exec.V.P.&amp; C.F.O./Pres.HHA</officerTitle></reportingOwnerRelationship></rep
ortingOwner><nonDerivativeTable><nonDerivativeTransaction><securityTitle><value>Common Stock</value></securityTitle><transactionDate><value>2003-12-01</value></transactionDate><deemedExecutionDate></deemedExecutionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>M</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionTimeliness><value></value></transactionTimeliness><transactionAmounts><transactionShares><value>25000.0000</value></transactionShares><transactionPricePerShare><value>17.5950</value><footnoteId id="F1" /></transactionPricePerShare><transactionAcquiredDisposedCode><value>A</value></transactionAcquiredDisposedCode></transactionAmounts><postTransactionAmounts><sharesOwnedFollowingTransaction><value>235912.0000</value><footnoteId id="F1" /></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership></ownershipNature></nonDerivativeTransaction
><nonDerivativeHolding><securityTitle><value>Common Stock - 401(k) Plan</value></securityTitle><postTransactionAmounts><sharesOwnedFollowingTransaction><value>5891.6533</value><footnoteId id="F2" /></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>I</value></directOrIndirectOwnership><natureOfOwnership><value>By 401(k)</value></natureOfOwnership></ownershipNature></nonDerivativeHolding></nonDerivativeTable><derivativeTable><derivativeTransaction><securityTitle><value>Employee Stock Option (right to buy)</value></securityTitle><conversionOrExercisePrice><value>17.5950</value><footnoteId id="F1" /></conversionOrExercisePrice><transactionDate><value>2003-12-01</value></transactionDate><deemedExecutionDate></deemedExecutionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>M</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionTimeliness><value></value></transactionTimeliness><trans
actionAmounts><transactionShares><value>25000.0000</value></transactionShares><transactionPricePerShare><value>0</value></transactionPricePerShare><transactionAcquiredDisposedCode><value>D</value></transactionAcquiredDisposedCode></transactionAmounts><exerciseDate><value>1999-01-07</value></exerciseDate><expirationDate><value>2004-01-06</value></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Common Stock</value></underlyingSecurityTitle><underlyingSecurityShares><value>25000.0000</value><footnoteId id="F1" /></underlyingSecurityShares></underlyingSecurity><postTransactionAmounts><sharesOwnedFollowingTransaction><value>27749.0000</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership></ownershipNature></derivativeTransaction></derivativeTable><footnotes><footnote id="F1">Number of shares and prices adjusted to reflect spin-off of Medco Health Solutions, Inc. on August 19, 2003.</footnote><foo
tnote id="F2">Includes shares acquired and dividends earned through October 1, 2003 in the Merck &amp; Co., Inc. Employee Savings and Security Plan, a 401(k) Plan.</footnote></footnotes><remarks></remarks><ownerSignature><signatureName>Judy C. Lewent</signatureName><signatureDate>2003-12-03</signatureDate></ownerSignature></ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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