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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2018-06-11</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001071993</issuerCik>
        <issuerName>CONTANGO OIL &amp; GAS CO</issuerName>
        <issuerTradingSymbol>MCF</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001040463</rptOwnerCik>
            <rptOwnerName>GOFF JOHN C</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>500 COMMERCE STREET,</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>FORT WORTH</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>76102</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001743422</rptOwnerCik>
            <rptOwnerName>Goff MCF Partners, LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>500 COMMERCE STREET</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 700</rptOwnerStreet2>
            <rptOwnerCity>FORT WORTH</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>76102</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001682344</rptOwnerCik>
            <rptOwnerName>Goff Capital, Inc.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>500 COMMERCE STREET</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 700</rptOwnerStreet2>
            <rptOwnerCity>FORT WORTH</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>76102</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001743461</rptOwnerCik>
            <rptOwnerName>John C. Goff 2010 Family Trust</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>500 COMMERCE STREET</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 700</rptOwnerStreet2>
            <rptOwnerCity>FORT WORTH</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>76102</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>2018-06-11</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>85000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>4.3959</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3186578</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnotes</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F6"/>
                    <footnoteId id="F7"/>
                    <footnoteId id="F8"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2018-06-12</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>95000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>4.4944</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3281578</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnotes</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F6"/>
                    <footnoteId id="F7"/>
                    <footnoteId id="F8"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>707881</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnotes</value>
                    <footnoteId id="F2"/>
                    <footnoteId id="F6"/>
                    <footnoteId id="F7"/>
                    <footnoteId id="F8"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>471921</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnotes</value>
                    <footnoteId id="F3"/>
                    <footnoteId id="F6"/>
                    <footnoteId id="F7"/>
                    <footnoteId id="F8"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>201950</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnotes</value>
                    <footnoteId id="F4"/>
                    <footnoteId id="F6"/>
                    <footnoteId id="F7"/>
                    <footnoteId id="F8"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>30000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnotes</value>
                    <footnoteId id="F5"/>
                    <footnoteId id="F6"/>
                    <footnoteId id="F7"/>
                    <footnoteId id="F8"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>8050</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By SEP IRA</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">These securities are held directly by Goff MCF Partners, LP (Goff MCF). Goff Capital, Inc. (Goff Capital) is the general partner of Goff MCF, and, as such, it may be deemed to beneficially own the securities held by Goff MCF. The John C. Goff 2010 Family Trust (the Trust) is the controlling shareholder of Goff Capital and, as such, it may be deemed to beneficially own the securities held by Goff Capital. John C. Goff is the trustee of the Trust and, as such, he may be deemed to beneficially own the securities held by the Trust.</footnote>
        <footnote id="F2">These securities are held directly by Goff REN Holdings, LLC (Goff REN). GFS REN GP, LLC (REN GP) is the managing member of Goff REN and, as such, it may be deemed to beneficially own the securities held by Goff REN. GFS Management, LLC (GFS Management) is the managing member of REN GP and, as such, it may be deemed to beneficially own the securities held by REN GP. Goff Focused Strategies, LLC (GFS) is the managing member of GFS Management and, as such, it may be deemed to beneficially own the securities held by GFS Management. GFT Strategies, LLC (GFT) is the controlling equity holder of GFS and, as such, it may be deemed to beneficially own the securities held by GFS. The Trust is the managing member of GFT and, as such, it may be deemed to beneficially own the securities held by GFT. John C. Goff is the trustee of the Trust and, as such, he may be deemed to beneficially own the securities held by the Trust.</footnote>
        <footnote id="F3">These securities are held directly by Goff REN II. REN GP is the managing member of Goff REN II and, as such, it may be deemed to beneficially own the securities held by Goff REN II. GFS Management is the managing member of REN GP and, as such, it may be deemed to beneficially own the securities held by REN GP. GFS is the managing member of GFS Management and, as such, it may be deemed to beneficially own the securities held by GFS Management. GFT is the controlling equity holder of GFS and, as such, it may be deemed to beneficially own the securities held by GFS. The Trust is the managing member of GFT and, as such, it may be deemed to beneficially own the securities held by GFT. John C. Goff is the trustee of the Trust and, as such, he may be deemed to beneficially own the securities held by the Trust.</footnote>
        <footnote id="F4">These securities are held directly by the Trust. John C. Goff is the trustee of the Trust and, as such, he may be deemed to beneficially own the securities held by the Trust.</footnote>
        <footnote id="F5">These shares are held directly by Goff Family Investments, LP (Goff Investments). Goff Capital is the general partner of Goff Investments and, as such, it may be deemed to beneficially own the securities held by the Goff Investments. The Trust is the controlling shareholder of Goff Capital and, as such, it may be deemed to beneficially own the securities held by Goff Capital. John C. Goff is the trustee of the Trust and, as such, he may be deemed to beneficially own the securities held by the Trust.</footnote>
        <footnote id="F6">Goff Capital, Goff REN, Goff REN II, REN GP, GFS, GFT, the Trust, Goff MCF, GFS Management, and Goff Investments may be considered a group under Section 13(d) of the Exchange Act; however, neither the fact of this filing nor anything contained herein shall be deemed to be an admission by such persons that such a group exists.</footnote>
        <footnote id="F7">For purposes of this filing, &quot;Reporting Persons&quot; means, as applicable, Goff MCF, Goff Capital, the Trust, and John C. Goff.</footnote>
        <footnote id="F8">The filing of this statement by the Reporting Persons shall not be deemed to be an admission that, for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or otherwise, such Reporting Persons are the beneficial owners of the securities reported herein and each of the Reporting Persons expressly disclaims beneficial ownership of the securities reported herein for purposes of Section 16 of the Securities Act, except to the extent of such Reporting Person's pecuniary interest therein.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>John C. Goff</signatureName>
        <signatureDate>2018-06-13</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Goff MCF Partners, LP, By: Goff Capital, Inc. is the general partner, By John C. Goff, President</signatureName>
        <signatureDate>2018-06-13</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Goff Capital, Inc., By: John C. Goff, President</signatureName>
        <signatureDate>2018-06-13</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>John C. Goff 2010 Family Trust, By: John C. Goff, Trustee</signatureName>
        <signatureDate>2018-06-13</signatureDate>
    </ownerSignature>
</ownershipDocument>
