Exhibit 99.1

CERTIFICATION PURSUANT TO
18 U.S.C. SECTION 1350,
AS ADOPTED PURSUANT TO
SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the Quarterly Report of OSI Systems, Inc. (the “Company”) on Form 10-Q for the period ending September 30, 2002 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), the undersigned, Deepak Chopra, Chief Executive Officer of the Company and Anuj Wadhawan, Chief Financial Officer of the Company, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that:

(1) The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

(2) The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

/s/ DEEPAK CHOPRA

Deepak Chopra
Chief Executive Officer
February 11, 2003

/s/ ANUJ WADHAWAN

Anuj Wadhawan
Chief Financial Officer
February 11, 2003