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Exhibit 23.1

Consent of Independent Registered Public Accounting Firm

        We hereby consent to the incorporation by reference in this Registration Statement on Form S-3 of our reports dated March 11, 2016, relating to the consolidated financial statements and the effectiveness of internal control over financial reporting, which appear in the Annual Report on Form 10-K of AXT, Inc. for the year ended December 31, 2015. We also consent to the reference of our firm under the heading "Experts" in such Registration Statement.

/s/ Burr Pilger Mayer, Inc.
San Jose, California
October 24, 2016

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Exhibit 23.1

Consent of Independent Registered Public Accounting Firm