-----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,
 B0/eatieP+PP8ugCzPNfUzkCoG3LXm96iXg67RwU9SB2W34TY6eE8DfKvJO1EtFa
 8fh2XDh1hkc2F+NNYfCF4g==

<SEC-DOCUMENT>0001140361-10-047214.txt : 20101124
<SEC-HEADER>0001140361-10-047214.hdr.sgml : 20101124
<ACCEPTANCE-DATETIME>20101124172025
ACCESSION NUMBER:		0001140361-10-047214
CONFORMED SUBMISSION TYPE:	4/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20101124
FILED AS OF DATE:		20101124
DATE AS OF CHANGE:		20101124

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			CHANG DAVID C
		CENTRAL INDEX KEY:			0001188184

	FILING VALUES:
		FORM TYPE:		4/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-24085
		FILM NUMBER:		101215686

	MAIL ADDRESS:	
		STREET 1:		C/O TIME WARNER CABLE INC.
		STREET 2:		60 COLUMBUS CIRCLE, 16TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10023

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			AXT INC
		CENTRAL INDEX KEY:			0001051627
		STANDARD INDUSTRIAL CLASSIFICATION:	SEMICONDUCTORS & RELATED DEVICES [3674]
		IRS NUMBER:				943031310
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		4281 TECHNOLOGY DR.
		CITY:			FREMONT
		STATE:			CA
		ZIP:			94538
		BUSINESS PHONE:		510.438.4734

	MAIL ADDRESS:	
		STREET 1:		4281 TECHNOLOGY DR.
		CITY:			FREMONT
		STATE:			CA
		ZIP:			94538

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	AMERICAN XTAL TECHNOLOGY
		DATE OF NAME CHANGE:	19971217
</SEC-HEADER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>doc1.xml
<DESCRIPTION>FORM 4/A
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2010-11-24</periodOfReport>

    <dateOfOriginalSubmission>2010-11-23</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001051627</issuerCik>
        <issuerName>AXT INC</issuerName>
        <issuerTradingSymbol>AXTI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001188184</rptOwnerCik>
            <rptOwnerName>CHANG DAVID C</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>4281 TECHNOLOGY DRIVE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>FREMONT</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94538</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>VP Global Sales &amp; Marketing</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>86312</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">On November 23, 2010, the reporting person mistakenly filed a Form 4 reporting a sale of 58,000 shares of common stock that did not in fact occur.  As of November 23, 2010, the reporting person should own 86,312 shares of common stock.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ David C. Chang by power of attorney</signatureName>
        <signatureDate>2010-11-24</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----
