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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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<SEC-DOCUMENT>0001209191-06-041005.txt : 20060712
<SEC-HEADER>0001209191-06-041005.hdr.sgml : 20060712
<ACCEPTANCE-DATETIME>20060712152954
ACCESSION NUMBER:		0001209191-06-041005
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20060710
FILED AS OF DATE:		20060712
DATE AS OF CHANGE:		20060712

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MODTECH HOLDINGS INC
		CENTRAL INDEX KEY:			0001075066
		STANDARD INDUSTRIAL CLASSIFICATION:	PREFABRICATED WOOD BLDGS & COMPONENTS [2452]
		IRS NUMBER:				330825386
		STATE OF INCORPORATION:			CA
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		2830 BARRETT AVE
		STREET 2:		PO BOX 1240
		CITY:			PERRIS
		STATE:			CA
		ZIP:			92571
		BUSINESS PHONE:		9099434014

	MAIL ADDRESS:	
		STREET 1:		4675 MACARTHUR CT.,
		STREET 2:		SUITE 710
		CITY:			NEWPORT
		STATE:			CA
		ZIP:			92660

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			WICK MYRON A III
		CENTRAL INDEX KEY:			0001080708

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-25161
		FILM NUMBER:		06958429

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		4159862215

	MAIL ADDRESS:	
		STREET 1:		50 OSGOOD PLACE
		CITY:			SAN FRANCISCO
		STATE:			CA
		ZIP:			94133
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2006-07-10</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001075066</issuerCik>
        <issuerName>MODTECH HOLDINGS INC</issuerName>
        <issuerTradingSymbol>MODT</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001080708</rptOwnerCik>
            <rptOwnerName>WICK MYRON A III</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>50 OSGOOD PLACE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SAN FRANCISCO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94133</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</value>
            </securityTitle>
            <transactionDate>
                <value>2006-07-10</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>8534</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>4.50</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>24434</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Options</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>4.50</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2006-07-10</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>D</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>8543</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>1997-07-11</value>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2006-07-10</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>8534</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>52273</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Became partially exercisable on July 11, 1997, one year after date of grant. Option is now fully vested.</footnote>
        <footnote id="F2">The total number of shares underlying all derivative securities held by the reporting person as of July 12, 2006 equaled 52,273.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Myron A. Wick, III</signatureName>
        <signatureDate>2006-07-12</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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