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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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<SEC-DOCUMENT>0000061986-04-000119.txt : 20040504
<SEC-HEADER>0000061986-04-000119.hdr.sgml : 20040504
<ACCEPTANCE-DATETIME>20040504160649
ACCESSION NUMBER:		0000061986-04-000119
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20040430
FILED AS OF DATE:		20040504

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			THROOP ROBERT S
		CENTRAL INDEX KEY:			0001205096

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-11978
		FILM NUMBER:		04777895

	BUSINESS ADDRESS:	
		STREET 1:		C/O MANITOWOC CO INC
		STREET 2:		P O BOX 66
		CITY:			MANITOWOC
		STATE:			WI
		ZIP:			54221-0066
		BUSINESS PHONE:		9206844410

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MANITOWOC CO INC
		CENTRAL INDEX KEY:			0000061986
		STANDARD INDUSTRIAL CLASSIFICATION:	CONSTRUCTION MACHINERY & EQUIP [3531]
		IRS NUMBER:				390448110
		STATE OF INCORPORATION:			WI
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		P O BOX 66
		CITY:			MANITOWOC
		STATE:			WI
		ZIP:			54221-0066
		BUSINESS PHONE:		9206844410

	MAIL ADDRESS:	
		STREET 1:		P O BOX 66
		CITY:			MANITOWOC
		STATE:			WI
		ZIP:			54221-0066
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2004-04-30</periodOfReport>

    <issuer>
        <issuerCik>0000061986</issuerCik>
        <issuerName>MANITOWOC CO INC</issuerName>
        <issuerTradingSymbol>MTW</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001205096</rptOwnerCik>
            <rptOwnerName>THROOP ROBERT S</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2400 SOUTH 44TH STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>MANITOWOC</rptOwnerCity>
            <rptOwnerState>WI</rptOwnerState>
            <rptOwnerZipCode>54221-0066</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2004-04-30</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>0.0206</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>30.55</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>49818.8147</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Common Stock Units acquired in transactions exempt under Rule 16b-3(d) under the Company's Deferred Compensation Plan.  This Plan provides for tax withholding rights.</footnote>
        <footnote id="F2">Includes 26,471.7941 shares which were previously reported on Table II as Common Stock Units held under the Company's Deferred Compensation Plan.  Following an amendment to that Plan, those Common Stock Units may only be automatically settled in common stock on a one-for-one basis.  Accordingly, those Common Stock Units may now be reported as the underlying shares on Table I.  (See American Bar Association, December 20, 1996)(Q.4(d)(3)).  In the future, additional acquisitions of Common Stock Units under the Plan will also be reported on Table I as directly owned shares of common stock.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Maurice D. Jones, by Power of Attorney</signatureName>
        <signatureDate>2004-05-04</signatureDate>
    </ownerSignature>
</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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