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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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 hEayjgsTj+gF5DKmJHuVVw==

<SEC-DOCUMENT>0001179110-10-015905.txt : 20101112
<SEC-HEADER>0001179110-10-015905.hdr.sgml : 20101111
<ACCEPTANCE-DATETIME>20101112120716
ACCESSION NUMBER:		0001179110-10-015905
CONFORMED SUBMISSION TYPE:	4/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20101027
FILED AS OF DATE:		20101112
DATE AS OF CHANGE:		20101112

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			GILEAD SCIENCES INC
		CENTRAL INDEX KEY:			0000882095
		STANDARD INDUSTRIAL CLASSIFICATION:	BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES) [2836]
		IRS NUMBER:				943047598
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		333 LAKESIDE DR
		CITY:			FOSTER CITY
		STATE:			CA
		ZIP:			94404
		BUSINESS PHONE:		6505743000

	MAIL ADDRESS:	
		STREET 1:		333 LAKESIDE DR
		CITY:			FOSTER CITY
		STATE:			CA
		ZIP:			94404

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BERG PAUL
		CENTRAL INDEX KEY:			0001198229

	FILING VALUES:
		FORM TYPE:		4/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-19731
		FILM NUMBER:		101184589

	MAIL ADDRESS:	
		STREET 1:		STANFORD UNIVERSITY SCHOOL OF MEDICINE
		STREET 2:		#B062
		CITY:			STANFORD
		STATE:			CA
		ZIP:			94305
</SEC-HEADER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 4/A -
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2010-10-27</periodOfReport>

    <dateOfOriginalSubmission>2010-10-29</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000882095</issuerCik>
        <issuerName>GILEAD SCIENCES INC</issuerName>
        <issuerTradingSymbol>GILD</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001198229</rptOwnerCik>
            <rptOwnerName>BERG PAUL</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>BECKMAN CENTER, RM. B062</rptOwnerStreet1>
            <rptOwnerStreet2>STANFORD UNIVERSITY SCHOOL OF MEDICINE</rptOwnerStreet2>
            <rptOwnerCity>STANFORD</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94305</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-10-27</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>12000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>39.2865</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>40006</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Sale prices reported for the transaction reported here range from $39.27 to $39.30. Full information regarding the number of shares purchased or sold at each price will be provided to the SEC, the issuer or its shareowners upon request.</footnote>
    </footnotes>

    <remarks>Amended Form 4 -    The reporting person is amending the Form 4 originally filed to report the sale transactions under Rule 144 and not pursuant to Dr. Bergs Rule 10b5-1 trading plan.</remarks>

    <ownerSignature>
        <signatureName>/s/ Paul Berg</signatureName>
        <signatureDate>2010-11-10</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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