<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2004-10-21</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000874992</issuerCik>
        <issuerName>REMINGTON OIL &amp; GAS CORP</issuerName>
        <issuerTradingSymbol>REM</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0000947911</rptOwnerCik>
            <rptOwnerName>SIMPLOT J R</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>999 MAIN ST</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>BOISE</rptOwnerCity>
            <rptOwnerState>IA</rptOwnerState>
            <rptOwnerZipCode>83702</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2004-10-21</value>
                <footnoteId id="F1"/>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>420000</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>26</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>4592595</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                    <footnoteId id="F2"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>FN 3</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Variable share postpaid forward sale of Common Stock</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>26</value>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2004-10-21</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>420000</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>26</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F1"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>420000</value>
                    <footnoteId id="F1"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>4592595</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See FN 2</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">See Explanation of Responses</footnote>
        <footnote id="F2">See Table I, Item 7</footnote>
        <footnote id="F3">4,592,595 shares are directly owned by JRS Properties III L.P. (&quot;JRS Properties III&quot;).  (Of these shares, 950,000 shares are subject to previously-reported variable share foward sale contract and 420,000 shares are subject to the variable share postpaid forward sale contract referenced in Table II and the &quot;Explanation of Responses.&quot;)  The J.R. Simplot Self Declaration of Revocable Trust (the &quot;Trust&quot;), of which Mr. J.R. Simplot is the beneficiary, and a trust for the benefit of Mrs. Simplot's spouse hold approximately 98% of the limited partnership interest in JRS Properties III and as such hold that percentage of pecuniary beneficial interest in the shares owned by JRS Properties III.</footnote>
    </footnotes>

    <remarks>JRS Properties III entered into a deferred sale transaction in the form of a variable share postpaid forward sale contract (&quot;Contract&quot;) with Merrill Lynch, Pierce, Fenner &amp; Smith (&quot;MLPFS&quot;) pursuant to which JRS Properties III is entitled to receive, at any time prior to or at the maturity date, part or all of a notional amount of cash against the future delivery of a variable number of up to 420,000 shares (collectively, the &quot;Shares&quot;) of Remington's Common Stock.  The actual price per share as well as the Floor, Cap and Post-Payment Amount payable to JRS Properties III will be determined on the Trade Date and will equal the applicable number of shares multiplied by the present value of the Floor Price (discounted by the prevailing LIBOR/Swap Rate for the remaining term of the transaction).  MLPFS commenced hedge transactions on October 21, 2004.  The Contract will mature in three installments at the end of 35, 36 and 37 months.</remarks>

    <ownerSignature>
        <signatureName>J.R. Simplot by Ronald N. Graves, as Attorney-in-Fact</signatureName>
        <signatureDate>2004-10-25</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>J.R. Simplot Self Declaration of Revocable Trust by J.R. Simplot, Trustee, by Ronald N. Graves, as Attorney-in-Fact</signatureName>
        <signatureDate>2004-10-25</signatureDate>
    </ownerSignature>
</ownershipDocument>

