<SEC-DOCUMENT>0001140361-14-008156.txt : 20140218
<SEC-HEADER>0001140361-14-008156.hdr.sgml : 20140217
<ACCEPTANCE-DATETIME>20140218075600
ACCESSION NUMBER:		0001140361-14-008156
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20140214
FILED AS OF DATE:		20140218
DATE AS OF CHANGE:		20140218

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			U.S. Auto Parts Network, Inc.
		CENTRAL INDEX KEY:			0001378950
		STANDARD INDUSTRIAL CLASSIFICATION:	RETAIL-AUTO & HOME SUPPLY STORES [5531]
		IRS NUMBER:				680623433
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1229

	BUSINESS ADDRESS:	
		STREET 1:		16941 KEEGAN AVE
		CITY:			CARSON
		STATE:			CA
		ZIP:			90746
		BUSINESS PHONE:		(310) 735-0085

	MAIL ADDRESS:	
		STREET 1:		16941 KEEGAN AVE
		CITY:			CARSON
		STATE:			CA
		ZIP:			90746

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Robson David
		CENTRAL INDEX KEY:			0001317553

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33264
		FILM NUMBER:		14620382

	MAIL ADDRESS:	
		STREET 1:		C/O GUITAR CENTER
		STREET 2:		5795 LINDERO CANYON RD.
		CITY:			WESTLAKE VILLAGE
		STATE:			CA
		ZIP:			91362
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc1.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2014-02-14</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001378950</issuerCik>
        <issuerName>U.S. Auto Parts Network, Inc.</issuerName>
        <issuerTradingSymbol>PRTS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001317553</rptOwnerCik>
            <rptOwnerName>Robson David</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O U.S. AUTO PARTS NETWORK, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>16941 KEEGAN AVENUE</rptOwnerStreet2>
            <rptOwnerCity>CARSON</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>90746</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Financial Officer</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable></nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Options (Right to Buy)</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>2.03</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2014-02-14</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>150000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2015-02-14</value>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2024-02-13</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>150000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>235714</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Granted pursuant to the U.S. Auto Parts Network, Inc. 2007 Omnibus Incentive Plan.</footnote>
        <footnote id="F2">Twenty-five percent of the shares of stock subject to the option vest on February 14, 2015, and thereafter the balance of the option shares vest and become exercisable in a series of thirty-six equal monthly installments over the following three year period, so that all of the shares of stock subject to the option vest on February 14, 2018, subject to the reporting person's continued service relationship with the issuer or any subsidiary of the issuer on each such date.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Bryan P. Stevenson, as Attorney-in-Fact for David Robson</signatureName>
        <signatureDate>2014-02-18</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
