<SUBMISSION>
<ACCESSION-NUMBER>0001020569-07-000020
<TYPE>3
<PUBLIC-DOCUMENT-COUNT>1
<PERIOD>20070423
<FILING-DATE>20070425
<DATE-OF-FILING-DATE-CHANGE>20070425
<ISSUER>
<COMPANY-DATA>
<CONFORMED-NAME>IRON MOUNTAIN INC
<CIK>0001020569
<ASSIGNED-SIC>4220
<IRS-NUMBER>232588479
<STATE-OF-INCORPORATION>DE
<FISCAL-YEAR-END>1231
</COMPANY-DATA>
<BUSINESS-ADDRESS>
<STREET1>745 ATLANTIC AVENUE
<CITY>BOSTON
<STATE>MA
<ZIP>02111
<PHONE>6175354766
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>745 ATLANTIC AVENUE
<CITY>BOSTON
<STATE>MA
<ZIP>02111
</MAIL-ADDRESS>
<FORMER-COMPANY>
<FORMER-CONFORMED-NAME>IRON MOUNTAIN INC/PA
<DATE-CHANGED>20000201
</FORMER-COMPANY>
<FORMER-COMPANY>
<FORMER-CONFORMED-NAME>PIERCE LEAHY CORP
<DATE-CHANGED>19960807
</FORMER-COMPANY>
</ISSUER>
<REPORTING-OWNER>
<OWNER-DATA>
<CONFORMED-NAME>MCKEON BRIAN P
<CIK>0001219445
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>3
<ACT>34
<FILE-NUMBER>001-13045
<FILM-NUMBER>07788026
</FILING-VALUES>
<MAIL-ADDRESS>
<STREET1>200 DOMAIN DR
<CITY>STRATHAM
<STATE>NH
<ZIP>03885
</MAIL-ADDRESS>
</REPORTING-OWNER>
<DOCUMENT>
<TYPE>3
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2007-04-23</periodOfReport>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0001020569</issuerCik>
        <issuerName>IRON MOUNTAIN INC</issuerName>
        <issuerTradingSymbol>IRM</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001219445</rptOwnerCik>
            <rptOwnerName>MCKEON BRIAN P</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>IRON MOUNTAIN INFORMATION MGMT, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>745 ATLANTIC AVENUE</rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02111</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>EVP &amp; CFO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock, par value, $.01 per share</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes></footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Brian P. McKeon</signatureName>
        <signatureDate>2007-04-25</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SUBMISSION>
