Iris International (IRIS) 10-Q 2006 Q3 Quarterly report

Exhibit 32.1

CERTIFICATION OF PRINCIPAL EXECUTIVE OFFICER

PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with Quarterly Report of IRIS International, Inc. (the “Company”) on Form 10-Q for the period ending September 30, 2006 as filed with the Securities and Exchange Commission on the date thereof (the “Report”), I, César M. García, Chief Executive 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, to the best of my knowledge:

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.

Dated: November 14, 2006

/s/ CESAR M. GARCIA

César M. García

Chief Executive Officer