<SUBMISSION>
<ACCESSION-NUMBER>0001186747-09-000005
<TYPE>4
<PUBLIC-DOCUMENT-COUNT>1
<PERIOD>20090102
<FILING-DATE>20090106
<DATE-OF-FILING-DATE-CHANGE>20090106
<REPORTING-OWNER>
<OWNER-DATA>
<CONFORMED-NAME>LARSON BRIAN A
<CIK>0001186747
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>4
<ACT>34
<FILE-NUMBER>001-12882
<FILM-NUMBER>09509705
</FILING-VALUES>
<BUSINESS-ADDRESS>
<STREET1>C/O BOYD GAMING CORP
<STREET2>2950 INDUSTRIAL ROAD
<CITY>LAS VEGAS
<STATE>NV
<ZIP>89109
<PHONE>7027927200
</BUSINESS-ADDRESS>
</REPORTING-OWNER>
<ISSUER>
<COMPANY-DATA>
<CONFORMED-NAME>BOYD GAMING CORP
<CIK>0000906553
<ASSIGNED-SIC>7990
<IRS-NUMBER>880242733
<STATE-OF-INCORPORATION>NV
<FISCAL-YEAR-END>1231
</COMPANY-DATA>
<BUSINESS-ADDRESS>
<STREET1>3883 HOWARD HUGHES PARKWAY
<STREET2>NINTH FLOOR
<CITY>LAS VEGAS
<STATE>NV
<ZIP>89169
<PHONE>7027927200
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>3883 HOWARD HUGHES PARKWAY
<STREET2>NINTH FLOOR
<CITY>LAS VEGAS
<STATE>NV
<ZIP>89169
</MAIL-ADDRESS>
<FORMER-COMPANY>
<FORMER-CONFORMED-NAME>BOYD GROUP
<DATE-CHANGED>19941130
</FORMER-COMPANY>
</ISSUER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2009-01-02</periodOfReport>

    <issuer>
        <issuerCik>0000906553</issuerCik>
        <issuerName>BOYD GAMING CORP</issuerName>
        <issuerTradingSymbol>BYD</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001186747</rptOwnerCik>
            <rptOwnerName>LARSON BRIAN A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>3883 HOWARD HUGHES PARKWAY</rptOwnerStreet1>
            <rptOwnerStreet2>NINTH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>LAS VEGAS</rptOwnerCity>
            <rptOwnerState>NV</rptOwnerState>
            <rptOwnerZipCode>89169</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Executive Vice President</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Career Restricted Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2009-01-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>12600</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F2"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>12600</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>12600</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The Career Restricted Stock Units were granted to the Reporting Person for no consideration pursuant to the Issuer's Career Shares Program under its 2002 Stock Incentive Plan.  Each Career Restricted Stock Unit represents a contingent right to receive one share of Issuer common stock.</footnote>
        <footnote id="F2">The Career Restricted Stock Units will be paid out in shares of Issuer common stock at the time of retirement based upon the Reporting Person's/grantee's attained age and years of continuous service at the time of retirement.  To receive any payout under the Career Shares Program, grantees must be at least 60 years old and must have been continually employed by the Issuer for a minimum of 15 years.  Retirement after 15 years of service will entitle a grantee to 50 percent of his or her Career Restricted Stock Units.  This increases to 75 percent after 20 years and 100 percent following 25 years of employment.  In the event of grantee's death or permanent disability, or following a change in control of Issuer, the grantee will be deemed to have attained age 60 and the Career Restricted Stock Units will immediately vest and convert into shares of Issuer common stock based on the grantee's years of continuous service through the date of death, termination resulting from permanent disability or the change in control, as applicable.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Brian A. Larson</signatureName>
        <signatureDate>2009-01-06</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SUBMISSION>
