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

    <documentType>4</documentType><periodOfReport>2003-08-27</periodOfReport>
    <issuer>
        <issuerCik>0001037646</issuerCik>
        <issuerName>METTLER TOLEDO INTERNATIONAL INC/</issuerName>
        <issuerTradingSymbol>MTD</issuerTradingSymbol></issuer><reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001207929</rptOwnerCik>
            <rptOwnerName>FILLIOL OLIVER A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>IM LANGACHER</rptOwnerStreet1>
            <rptOwnerStreet2>CH-8606 GREIFENSEE</rptOwnerStreet2>
            <rptOwnerCity>SWITZERLAND</rptOwnerCity>
            <rptOwnerState></rptOwnerState>
            <rptOwnerZipCode></rptOwnerZipCode>
            <rptOwnerStateDescription>SWITZERLAND</rptOwnerStateDescription>
        </reportingOwnerAddress>
            <reportingOwnerRelationship>
<isDirector>0</isDirector><isOfficer>1</isOfficer><isTenPercentOwner>0</isTenPercentOwner><isOther>0</isOther><officerTitle>Head of Process Analytics</officerTitle></reportingOwnerRelationship></reportingOwner><derivativeTable><derivativeTransaction><securityTitle><value>Stock Option (right to buy)</value></securityTitle><conversionOrExercisePrice><value>37.56</value></conversionOrExercisePrice><transactionDate><value>2003-08-27</value></transactionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>A</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionAmounts><transactionShares><value>45000</value></transactionShares><transactionPricePerShare><value>0</value></transactionPricePerShare><transactionAcquiredDisposedCode><value>A</value></transactionAcquiredDisposedCode></transactionAmounts><exerciseDate><value>2004-08-27</value><footnoteId id="F1"/></exerciseDate><expirationDate><value>2014-02-27</value></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Common Stock, par value $0.01 per share</value></underlyingSecurityTitle><underlyingSecurityShares><value>45000</value></underlyingSecurityShares></underlyingSecurity><postTransactionAmounts><sharesOwnedFollowingTransaction><value>45000</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value/></natureOfOwnership></ownershipNature></derivativeTransaction></derivativeTable><footnotes><footnote id="F1">30,000 of the options vest annually in five equal installments beginning on the first anniversary of the date of grant.  In addition, 15,000 of the options vest annually in three equal installments beginning on the third anniversary of the date of grant; provided that if certain 2003 financial targets are met, these options would vest annually in two equal installments beginning on the first anniversary of the date of grant.  In addition, all the options vest fully upon certain events, including the merger, consolidation or change in control of the company.</footnote></footnotes><remarks/><ownerSignature><signatureName>James Bellerjeau, Attorney in Fact</signatureName><signatureDate>2003-08-29</signatureDate></ownerSignature></ownershipDocument>

