Exhibit 32.1

Certification of Chief Executive Officer and Chief Financial Officer

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 Annual Report of Rosetta Resources Inc. (the “Company”) on Form 10-K for the period ended December 31, 2008 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), each of the undersigned officers of the Company certifies, pursuant to 18 U.S.C. § 1350, as adopted pursuant to § 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.

Date: February __, 2008	/s/ Randy L. Limbacher
	Randy L. Limbacher
	President and Chief Executive Officer
	/s/ Michael J. Rosinski
	Michael J. Rosinski
	Executive Vice President and Chief Financial Officer