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, 2011 (“Form 10-K”), each of the undersigned officers of the Company certifies pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, 18 U.S.C. Section 1350, that to the best of such officer’s knowledge: (i) the Form 10-K fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended; and (ii) the information contained in the Form 10-K fairly presents, in all material respects, the financial condition and results of operations of the Company.

Date: February 27, 2012	By: /s/ RANDY L. LIMBACHER
	Randy L. Limbacher
	Chairman of the Board, Chief Executive Officer and President
	By: /s/ JOHN E. HAGALE
	John E. Hagale
	Executive Vice President, Chief Financial Officer and Treasurer

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