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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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 OmLUEgzzEMiReYNZb+s6RA==

<SEC-DOCUMENT>0001104659-08-045665.txt : 20080715
<SEC-HEADER>0001104659-08-045665.hdr.sgml : 20080715
<ACCEPTANCE-DATETIME>20080715122917
ACCESSION NUMBER:		0001104659-08-045665
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080711
FILED AS OF DATE:		20080715
DATE AS OF CHANGE:		20080715

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MARVELL TECHNOLOGY GROUP LTD
		CENTRAL INDEX KEY:			0001058057
		STANDARD INDUSTRIAL CLASSIFICATION:	SEMICONDUCTORS & RELATED DEVICES [3674]
		IRS NUMBER:				770481679
		STATE OF INCORPORATION:			D0
		FISCAL YEAR END:			0131

	BUSINESS ADDRESS:	
		STREET 1:		CANON'S COURT
		STREET 2:		22 VICTORIA STREET
		CITY:			HAMILTON HM 12
		STATE:			D0
		BUSINESS PHONE:		4412966395

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			GROMER JURGEN W K
		CENTRAL INDEX KEY:			0001223630

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-30877
		FILM NUMBER:		08952344

	MAIL ADDRESS:	
		STREET 1:		C/O TYCO ELECTRONICS CORP
		STREET 2:		2901 FULLING MILL RD
		CITY:			MIDDLETOWN
		STATE:			PA
		ZIP:			17057
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>a4.xml
<DESCRIPTION>4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-07-11</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001058057</issuerCik>
        <issuerName>MARVELL TECHNOLOGY GROUP LTD</issuerName>
        <issuerTradingSymbol>MRVL</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001223630</rptOwnerCik>
            <rptOwnerName>GROMER JURGEN W K</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O 5488 MARVELL LANE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SANTA CLARA</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>95054</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>15.36</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2008-07-11</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>12000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2018-07-11</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Shares</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>12000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>12000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Vests 100% of shares on the earlier of the next annual general meeting of Marvell or the one year anniversary of the option grant date.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Juergen W. Gromer</signatureName>
        <signatureDate>2008-07-12</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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