EXHIBIT 32.1

CERTIFICATION

PURSUANT TO

18 U.S.C. SECTION 1350

The undersigned, Oleg Khaykin, the Chief Executive Officer of International Rectifier Corporation (the “Company”), pursuant to 18 U.S.C. §1350, hereby certifies that:

(i) the Quarterly Report on Form 10-Q of the Company for the fiscal quarter ended December 27, 2009 (the “Report”) fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

(ii) the information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company as of, and for, the periods presented in the Report.

Date: February 3, 2010	/s/ OLEG KHAYKIN
	Oleg Khaykin Chief Executive Officer (Principal Executive Officer)