<SEC-DOCUMENT>0001527802-12-000005.txt : 20120703
<SEC-HEADER>0001527802-12-000005.hdr.sgml : 20120703
<ACCEPTANCE-DATETIME>20120703145658
ACCESSION NUMBER:		0001527802-12-000005
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		2
CONFORMED PERIOD OF REPORT:	20120702
FILED AS OF DATE:		20120703
DATE AS OF CHANGE:		20120703

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ROMEO DOMINIC A
		CENTRAL INDEX KEY:			0001276009

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-35083
		FILM NUMBER:		12944194

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			GSI GROUP INC
		CENTRAL INDEX KEY:			0001076930
		STANDARD INDUSTRIAL CLASSIFICATION:	MISCELLANEOUS ELECTRICAL MACHINERY, EQUIPMENT & SUPPLIES [3690]
		IRS NUMBER:				980110412
		STATE OF INCORPORATION:			A3
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		125 MIDDLESEX TURNPIKE
		STREET 2:		.
		CITY:			BEDFORD
		STATE:			MA
		ZIP:			01730
		BUSINESS PHONE:		781-266-5618

	MAIL ADDRESS:	
		STREET 1:		125 MIDDLESEX TURNPIKE
		STREET 2:		.
		CITY:			BEDFORD
		STATE:			MA
		ZIP:			01730

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	GSI LUMONICS INC
		DATE OF NAME CHANGE:	19990401

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	GSI LUMONICS
		DATE OF NAME CHANGE:	19990331

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	LUMONICS INC
		DATE OF NAME CHANGE:	19990115
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2012-07-02</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001076930</issuerCik>
        <issuerName>GSI GROUP INC</issuerName>
        <issuerTradingSymbol>GSIG</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001276009</rptOwnerCik>
            <rptOwnerName>ROMEO DOMINIC A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>GSI GROUP INC.</rptOwnerStreet1>
            <rptOwnerStreet2>125 MIDDLESEX TURNPIKE</rptOwnerStreet2>
            <rptOwnerCity>BEDFORD</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>01730</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Deferred Stock Unit</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2012-07-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>2982</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F1"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>2982</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2982</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">As of the date the reporting person ceases to be a director, each DSU shall convert into 1 share of issuer common stock.</footnote>
    </footnotes>

    <remarks>Exhibit 24 - Power of Attorney</remarks>

    <ownerSignature>
        <signatureName>Paula A. Pluta, Attorney-in-Fact</signatureName>
        <signatureDate>2012-07-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-24
<SEQUENCE>2
<FILENAME>romeodominicasecpoa.txt
<TEXT>
POWER OF ATTORNEY




      Know all by these presents that the
undersigned hereby constitutes and appoints
Robert Buckley, Paula A. Pluta and Joanna Tow
as his true and lawful attorneys-in-fact to:
(1)	execute for and on behalf
of the undersigned Forms
3, 4 and 5 in accordance
with Section 16(a) of the
Securities Exchange Act
of 1934, as amended, and
the rules thereunder, for
and in relation to any and
all reportable transactions
in the securities of GSI
Group, Inc.;
(2)	do and perform any and
all acts for and on behalf
of the undersigned which
may be necessary or
desirable to complete the
execution of any such
Form 3, 4 and 5 and
timely filing of such forms
with the United States
Securities and Exchange
Commission and any other
authority; and
(3)	take any other action of
any type whatsoever in
connection with the
foregoing which, in the
opinion of such attorneys-
in-fact, may be of benefit
to, in the best interest of,
or legally required by, the
undersigned, it being
understood that the
documents executed by
such attorneys-in-fact on
behalf of the undersigned
pursuant to this Power of
Attorney shall be in such
form and shall contain
such terms and conditions
as such attorneys-in-fact
may approve in their
discretion.
      The undersigned hereby grants to each
attorney-in-fact, individually, full power and
authority to do and perform all and every act and
thing whatsoever requisite, necessary and proper
to be done in the exercise of any of the rights and
powers herein granted, as fully to all intents and
purposes as each attorney-in-fact might or could
do if personally present, with full power of
substitution or revocation, hereby ratifying and
confirming that each attorney-in-fact, or his
substitute or substitutes, shall lawfully do or
cause to be done by virtue of this power of
attorney and the rights and powers herein
granted.  The undersigned acknowledges that the
foregoing attorneys-in-fact, in serving in such
capacity at the request of the undersigned, are
not assuming any of the undersigned's
responsibilities to comply with Section 16 of the
Securities Exchange Act of 1934, as amended.
      IN WITNESS WHEREOF, the
undersigned has caused this Power of Attorney
to be executed as of this ____ day of June, 2012.


	/s/
Dominic A. Romeo
	Sig
nature

	Do
minic A. Romeo
	Prin
t Name
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
