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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>0001019687-07-003324.txt : 20071002
<SEC-HEADER>0001019687-07-003324.hdr.sgml : 20071002
<ACCEPTANCE-DATETIME>20071002210743
ACCESSION NUMBER:		0001019687-07-003324
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20070928
FILED AS OF DATE:		20071002
DATE AS OF CHANGE:		20071002

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Gelbaum David
		CENTRAL INDEX KEY:			0001391795

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-22175
		FILM NUMBER:		071151840

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		949-646-3784

	MAIL ADDRESS:	
		STREET 1:		2309 SANTIAGO DRIVE
		CITY:			NEWPORT BEACH
		STATE:			CA
		ZIP:			92660

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Gelbaum Monica Chavez
		CENTRAL INDEX KEY:			0001403417

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-22175
		FILM NUMBER:		071151838

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		760-942-0157

	MAIL ADDRESS:	
		STREET 1:		2309 SANTIAGO DRIVE
		CITY:			NEWPORT BEACH
		STATE:			CA
		ZIP:			92660

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			EMCORE CORP
		CENTRAL INDEX KEY:			0000808326
		STANDARD INDUSTRIAL CLASSIFICATION:	SEMICONDUCTORS & RELATED DEVICES [3674]
		IRS NUMBER:				222746503
		STATE OF INCORPORATION:			NJ
		FISCAL YEAR END:			0930

	BUSINESS ADDRESS:	
		STREET 1:		145 BELMONT DRIVE
		CITY:			SOMERSET
		STATE:			NJ
		ZIP:			08873
		BUSINESS PHONE:		7322719090

	MAIL ADDRESS:	
		STREET 1:		145 BELMONT DRIVE
		CITY:			SOMERSET
		STATE:			NJ
		ZIP:			08873

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Quercus Trust
		CENTRAL INDEX KEY:			0001403463
		STATE OF INCORPORATION:			CA
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-22175
		FILM NUMBER:		071151839

	BUSINESS ADDRESS:	
		STREET 1:		2309 SANTIAGO DRIVE
		CITY:			NEWPORT BEACH
		STATE:			CA
		ZIP:			92660
		BUSINESS PHONE:		310-201-7481

	MAIL ADDRESS:	
		STREET 1:		2309 SANTIAGO DRIVE
		CITY:			NEWPORT BEACH
		STATE:			CA
		ZIP:			92660
</SEC-HEADER>
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<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2007-09-28</periodOfReport>

    <issuer>
        <issuerCik>0000808326</issuerCik>
        <issuerName>EMCORE CORP</issuerName>
        <issuerTradingSymbol>EMKR</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001403463</rptOwnerCik>
            <rptOwnerName>Quercus Trust</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2309 SANTIAGO DR.</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>NEWPORT BEACH</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92660</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001391795</rptOwnerCik>
            <rptOwnerName>Gelbaum David</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2309 SANTIAGO DR.</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>NEWPORT BEACH,</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92660</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>1</isOther>
            <otherText>Co-Trustee</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001403417</rptOwnerCik>
            <rptOwnerName>Gelbaum Monica Chavez</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2309 SANTIAGO DR.</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>NEWPORT BEACH,</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92660</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>1</isOther>
            <otherText>Co-Trustee</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2007-09-28</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>127650</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>9.5882</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>5310777</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2007-10-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>173800</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>10.0448</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>5484577</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2007-10-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>198550</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>10.5088</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>5683127</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes></footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ David Gelbaum, Co-Trustee, The Quercus Trust</signatureName>
        <signatureDate>2007-10-02</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ David Gelbaum, as attorney-in-fact for Monica Chavez Gelbaum, Co-Trustee, The Quercus Trust</signatureName>
        <signatureDate>2007-10-02</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----