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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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<SEC-DOCUMENT>0001140361-04-001663.txt : 20040301
<SEC-HEADER>0001140361-04-001663.hdr.sgml : 20040301
<ACCEPTANCE-DATETIME>20040301172004
ACCESSION NUMBER:		0001140361-04-001663
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20040229
FILED AS OF DATE:		20040301

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			LATHAM DAN
		CENTRAL INDEX KEY:			0001241880

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-15423
		FILM NUMBER:		04640262

	MAIL ADDRESS:	
		STREET 1:		1330 POST OAK BLVD
		STREET 2:		STE 2700
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77056

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			GRANT PRIDECO INC
		CENTRAL INDEX KEY:			0001097313
		STANDARD INDUSTRIAL CLASSIFICATION:	OIL & GAS FILED MACHINERY & EQUIPMENT [3533]
		IRS NUMBER:				760312499
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1450 LAKE ROBBINS DRIVE
		STREET 2:		SUITE 600
		CITY:			THE WOODLANDS
		STATE:			TX
		ZIP:			77038
		BUSINESS PHONE:		2812978500

	MAIL ADDRESS:	
		STREET 1:		1450 LAKE ROBBINS DRIVE
		STREET 2:		SUITE 600
		CITY:			THE WOODLANDS
		STATE:			TX
		ZIP:			77038
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc1.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0201</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2004-02-29</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001097313</issuerCik>
        <issuerName>GRANT PRIDECO INC</issuerName>
        <issuerTradingSymbol>GRP</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001241880</rptOwnerCik>
            <rptOwnerName>LATHAM DAN</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1330 POST OAK BLVD</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 2700</rptOwnerStreet2>
            <rptOwnerCity>HOUSTON</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>77056</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Pres Drilling Products</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Phantom Stock Units</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2004-02-29</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>303.9448</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>14.1221</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>303.9448</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>20433.6126</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Represents units credited to the participants account pursuant to the terms of the Companys Executive Deferred Compensation Plan. All phantom stock units credited under the Plan with respect to deferrals of compensation by participants are 100% vested at all times.  All units credited under the Plan with respect to the Company's 7.5% allocation and matching allocation vest at 20% per year for each year of service with the Company.  Distributions under the Plan are made upon termination of employment, retirement or death of the participant.  Units are allocated at month-end based upon the fair market value of the common stock at month end.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Philip A. Choyce, Attorney in Fact</signatureName>
        <signatureDate>2004-03-01</signatureDate>
    </ownerSignature>
</ownershipDocument>

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