<?xml version="1.0"?>
<ownershipDocument>
    <schemaVersion>X0201</schemaVersion>

    <documentType>4</documentType><periodOfReport>2004-01-16</periodOfReport>
    <issuer>
        <issuerCik>0000063754</issuerCik>
        <issuerName>MCCORMICK &amp; CO INC</issuerName>
        <issuerTradingSymbol>MKC</issuerTradingSymbol></issuer><reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001261238</rptOwnerCik>
            <rptOwnerName>PRESTON MARGARET M V</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>MCCORMICK &amp; COMPANY, INCORPORATED</rptOwnerStreet1>
            <rptOwnerStreet2>18 LOVETON CIRCLE</rptOwnerStreet2>
            <rptOwnerCity>SPARKS</rptOwnerCity>
            <rptOwnerState>MD</rptOwnerState>
            <rptOwnerZipCode>21152</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
            <reportingOwnerRelationship>
<isDirector>1</isDirector><isOfficer>0</isOfficer><isTenPercentOwner>0</isTenPercentOwner><isOther>0</isOther></reportingOwnerRelationship></reportingOwner><nonDerivativeTable><nonDerivativeTransaction><securityTitle><value>Common Stock - Voting</value></securityTitle><transactionDate><value>2004-01-16</value></transactionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>A</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionAmounts><transactionShares><value>8.304</value></transactionShares><transactionPricePerShare><value>28.90</value></transactionPricePerShare><transactionAcquiredDisposedCode><value>A</value></transactionAcquiredDisposedCode></transactionAmounts><postTransactionAmounts><sharesOwnedFollowingTransaction><value>8.304</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>I</value></directOrIndirectOwnership><natureOfOwnership><value>Deferred Compensation Plan</value></natureOfOwnership></ownershipNature></nonDerivativeTransaction></nonDerivativeTable><footnotes/><remarks/><ownerSignature><signatureName>W. Geoffrey Carpenter, Attorney-in-Fact</signatureName><signatureDate>2004-01-20</signatureDate></ownerSignature></ownershipDocument>

