-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
 MFgwCgYEVQgBAQICAf8DSgAwRwJAW2sNKK9AVtBzYZmr6aGjlWyK3XmZv3dTINen
 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 UrSv/AUCgSNhJItMU8qVeKAEjwjEz9fLHyQDrTf0FMrofAAH7HYqsn66LN0pqPuT
 k3tVevAvg4G7oap/xNOoIQ==

<SEC-DOCUMENT>0001104659-11-002703.txt : 20110124
<SEC-HEADER>0001104659-11-002703.hdr.sgml : 20110124
<ACCEPTANCE-DATETIME>20110124213759
ACCESSION NUMBER:		0001104659-11-002703
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20110120
FILED AS OF DATE:		20110124
DATE AS OF CHANGE:		20110124

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Chin Lanfang (Lydia)
		CENTRAL INDEX KEY:			0001506240

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34992
		FILM NUMBER:		11544942

	MAIL ADDRESS:	
		STREET 1:		3F, NO. 11 KE JUNG RD., CHU-NAN SITE
		STREET 2:		HSINCHU SCIENCE PARK, MIAO-LI COUNTY
		CITY:			CHU-NAN
		STATE:			F5
		ZIP:			350

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			SemiLEDs Corp
		CENTRAL INDEX KEY:			0001333822
		STANDARD INDUSTRIAL CLASSIFICATION:	SEMICONDUCTORS & RELATED DEVICES [3674]
		IRS NUMBER:				202735523

	BUSINESS ADDRESS:	
		STREET 1:		3F, NO. 11 KE JUNG RD., CHU-NAN SITE
		STREET 2:		HSINCHU SCIENCE PARK, MIAO-LI COUNTY
		CITY:			CHU-NAN
		STATE:			F5
		ZIP:			350
		BUSINESS PHONE:		886-37-586788

	MAIL ADDRESS:	
		STREET 1:		3F, NO. 11 KE JUNG RD., CHU-NAN SITE
		STREET 2:		HSINCHU SCIENCE PARK, MIAO-LI COUNTY
		CITY:			CHU-NAN
		STATE:			F5
		ZIP:			350
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>a4.xml
<DESCRIPTION>4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2011-01-20</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001333822</issuerCik>
        <issuerName>SemiLEDs Corp</issuerName>
        <issuerTradingSymbol>LEDS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001506240</rptOwnerCik>
            <rptOwnerName>Chin Lanfang (Lydia)</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>3F, NO. 11 KE JUNG RD., CHU-NAN SITE</rptOwnerStreet1>
            <rptOwnerStreet2>HSINCHU SCIENCE PARK, MIAO-LI COUNTY</rptOwnerStreet2>
            <rptOwnerCity>CHU-NAN</rptOwnerCity>
            <rptOwnerState>F5</rptOwnerState>
            <rptOwnerZipCode>350</rptOwnerZipCode>
            <rptOwnerStateDescription>TAIWAN, PROVINCE OF CHINA</rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>General Counsel</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Employee Stock Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>19</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2011-01-20</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>12500</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2021-01-19</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>12500</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>12500</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">25% of the option vests and becomes exercisable upon the completion of each of 4 years of service following January 20, 2011 and will become fully vested and exercisable upon a change in control.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Lanfang (Lydia) Chin</signatureName>
        <signatureDate>2011-01-24</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----
