-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 Mn3Vzc0mQnnLAsaOIlLLnJIObZroHB5mYEv1fcyqMGwbyf4mY0W0jyoIvLjEyFI/
 OnH8XIsK9CHbNJuGGxyCOQ==

<SEC-DOCUMENT>0000936822-03-000010.txt : 20030903
<SEC-HEADER>0000936822-03-000010.hdr.sgml : 20030903
<ACCEPTANCE-DATETIME>20030903100246
ACCESSION NUMBER:		0000936822-03-000010
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20030829
FILED AS OF DATE:		20030903

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MERRILL LYNCH & CO INC
		CENTRAL INDEX KEY:			0000065100
		STANDARD INDUSTRIAL CLASSIFICATION:	SECURITY BROKERS, DEALERS & FLOTATION COMPANIES [6211]
		IRS NUMBER:				132740599
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		4 WORLD FINANCIAL CTR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10080
		BUSINESS PHONE:		2124491000

	MAIL ADDRESS:	
		STREET 1:		4 WORLD FINANCIAL CTR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10080

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			CRIBIORE ALBERTO
		CENTRAL INDEX KEY:			0000936822

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-14537
		FILM NUMBER:		03877644

	BUSINESS ADDRESS:	
		STREET 1:		712 FIFTH AVENUE 34TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10022
		BUSINESS PHONE:		2128351350

	MAIL ADDRESS:	
		STREET 1:		C/O SKADDEN ARPS SLATE MEAGHER & FLOM
		STREET 2:		333 WEST WACKER DR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10022
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>

<ownershipDocument>

    <schemaVersion>X0201</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2003-08-29</periodOfReport>


    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000065100</issuerCik>
        <issuerName>MERRILL LYNCH &amp; CO INC</issuerName>
        <issuerTradingSymbol>MER</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0000936822</rptOwnerCik>
            <rptOwnerName>CRIBIORE ALBERTO</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O MERRILL LYNCH &amp; CO., INC.</rptOwnerStreet1>
            <rptOwnerStreet2>4 WORLD FINANCIAL CENTER</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10080</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>

        <derivativeTransaction>
            <securityTitle>
                <value>ML Stock Units</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F2"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2003-08-29</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>117</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>53.32</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F1"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>117</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>366</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>

    </derivativeTable>

    <footnotes>
        <footnote id="F1">The reporting person participates in the Merrill Lynch &amp; Co., Inc. Fee Deferral Plan for Non-Employee Directors (the &quot;Fee Deferral Plan&quot;), under which these ML Stock Units were credited.  Transactions under the Fee Deferral Plan are exempt under Rule 16b-3.  The value of each unit is equal to the value of one share of Merrill Lynch &amp; Co., Inc. Common Stock.  ML Stock Units are payable in cash at the end of the deferral period as provided in the Fee Deferral Plan.</footnote>
        <footnote id="F2">1 for 1</footnote>
        <footnote id="F3">This total also reflects the reinvestment of dividend equivalents into ML Stock Units pursuant to the terms of the Fee Deferral Plan. This transaction is exempt from reporting pursuant to Rule 16a-3 and/or 16a-11.</footnote>
    </footnotes>

    <remarks>All reported positions have been rounded down to the nearest whole number.</remarks>

    <ownerSignature>
        <signatureName>Alberto Cribiore                              (by Michael A. LaMaina, as agent)</signatureName>
        <signatureDate>2003-09-03</signatureDate>
    </ownerSignature>

</ownershipDocument>

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