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Exhibit 32.1

Certification Pursuant To Section 906
of the Sarbanes-Oxley Act of 2002

        We hereby certify that the accompanying Report of Quanex Corporation on Form 10-K for the year ended October 31, 2003 fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934 and that information contained in such Report fairly presents, in all material respects, the financial condition and results of operations of Quanex Corporation.

December 22, 2003

/s/  RAYMOND A. JEAN Raymond A. Jean
Chairman of the Board, President and
Chief Executive Officer /s/  TERRY M. MURPHY Terry M. Murphy
Vice President—Finance and
Chief Financial Officer

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Certification Pursuant To Section 906 of the Sarbanes-Oxley Act of 2002