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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2017-02-24</periodOfReport>

    <notSubjectToSection16>1</notSubjectToSection16>

    <issuer>
        <issuerCik>0001009976</issuerCik>
        <issuerName>COMMERCIAL BANCSHARES INC \OH\</issuerName>
        <issuerTradingSymbol>CMOH</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001393963</rptOwnerCik>
            <rptOwnerName>Kinnett Stanley K</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1020 RAINBOW CT.</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>BRADENTON</rptOwnerCity>
            <rptOwnerState>FL</rptOwnerState>
            <rptOwnerZipCode>34212</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chairman of Board</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2017-02-24</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>D</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>8179.5447</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Shares held under deferred compensation plan</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F3"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2017-02-24</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>D</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>5107.0364</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F5"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F4"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F4"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>5107.0364</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Held in rabbi trust</value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Includes 34.0011 shares acquired under the Issuer's dividend reinvestment program covering dividends paid in 2016.</footnote>
        <footnote id="F2">Under the terms of the merger agreement with First Defiance Financial Corp., each shareholder of the Issuer has the right to elect to receive either $51.00 in cash or 1.1808 shares of First Defiance common stock (or a combination thereof) in exchange for each share of Issuer common owned.  All elections are subject to certain adjustments under the merger agreement necessary to cause 80% of the total consideration to be paid in First Defiance Shares and the remaining 20% of the total consideration to be paid in cash.  The insider has made an election to dispose of these shares in exchange for First Defiance Shares, but the adjustments required under the terms of the merger agreement have yet to be finalized.</footnote>
        <footnote id="F3">Each unit credited to participant under this plan is the economic equivalent of one of issuer's common shares.</footnote>
        <footnote id="F4">These shares are vested immediately and participant account balances are payable upon termination of service on the Company's Board of Directors.</footnote>
        <footnote id="F5">Under the terms of the merger agreement with First Defiance Financial Corp., each shareholder of the Issuer has the right to elect to receive either $51.00 in cash or 1.1808 shares of First Defiance common stock (or a combination thereof) in exchange for each share of Issuer common owned. All elections are subject to certain adjustments under the merger agreement necessary to cause 80% of the total consideration to be paid in First Defiance Shares and the remaining 20% of the total consideration to be paid in cash. The insider has made an election to dispose of 2,107.0364 of these shares in exchange for cash and 3,000 of these shares in exchange for First Defiance Shares, but the adjustments required under the terms of the merger agreement have yet to be finalized.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ David J. Browne as power of attorney for Stanley K. Kinnett</signatureName>
        <signatureDate>2017-02-27</signatureDate>
    </ownerSignature>
</ownershipDocument>
