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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 BemKLoh2dTa4t7q6uAzL5zNCpPAX83f4eYAOualKxznNfVD74bLgqxuRy2lIyrRc
 Ysp009D8c2Y07k7P4uxlnA==

<SEC-DOCUMENT>0001480248-10-000103.txt : 20100916
<SEC-HEADER>0001480248-10-000103.hdr.sgml : 20100916
<ACCEPTANCE-DATETIME>20100916134113
ACCESSION NUMBER:		0001480248-10-000103
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100916
FILED AS OF DATE:		20100916
DATE AS OF CHANGE:		20100916

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Conaway John Michal
		CENTRAL INDEX KEY:			0001351138

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34133
		FILM NUMBER:		101075550

	MAIL ADDRESS:	
		STREET 1:		QUANTA SERVICES, INC.
		STREET 2:		1360 POST OAK BLVD., SUITE 2100
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77056-3023

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			GT Solar International, Inc.
		CENTRAL INDEX KEY:			0001394954
		STANDARD INDUSTRIAL CLASSIFICATION:	SEMICONDUCTORS & RELATED DEVICES [3674]
		IRS NUMBER:				030606749
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0331

	BUSINESS ADDRESS:	
		STREET 1:		243 DANIEL WEBSTER HIGHWAY
		CITY:			MERRIMACK
		STATE:			NH
		ZIP:			03054
		BUSINESS PHONE:		(603)883-5200

	MAIL ADDRESS:	
		STREET 1:		243 DANIEL WEBSTER HIGHWAY
		CITY:			MERRIMACK
		STATE:			NH
		ZIP:			03054
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-09-16</periodOfReport>

    <issuer>
        <issuerCik>0001394954</issuerCik>
        <issuerName>GT Solar International, Inc.</issuerName>
        <issuerTradingSymbol>SOLR</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001351138</rptOwnerCik>
            <rptOwnerName>Conaway John Michal</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>GT  SOLAR INTERNATIONAL, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>243 DANIEL WEBSTER HIGHWAY</rptOwnerStreet2>
            <rptOwnerCity>MERRIMACK</rptOwnerCity>
            <rptOwnerState>NH</rptOwnerState>
            <rptOwnerZipCode>03054</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, Par Value $.01</value>
            </securityTitle>
            <transactionDate>
                <value>2010-09-16</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>9000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>7.78</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>17231</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes></footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/Allison G. Pellegrino, under power of attorney</signatureName>
        <signatureDate>2010-09-16</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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