Exhibit 32

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 Annual Report of Rio Vista Energy Partners L.P. (“Rio Vista”) on Form 10-K for the year ended December 31, 2007 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), the undersigned, Ian T. Bothwell, Acting Chief Executive Officer of Rio Vista GP LLC, the General Partner of Rio Vista, and Ian T. Bothwell, Chief Financial Officer of Rio Vista GP LLC, the General Partner of Rio Vista 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/ Ian T. Bothwell  

Ian T. Bothwell, Acting Chief Executive 

Officer of Rio Vista GP LLC, the general partner of Rio Vista Energy Partners L.P. 
April 15, 2008

/s/ Ian T. Bothwell  

Ian T. Bothwell, Chief Financial Officer of 

Rio Vista GP LLC, the General Partner of Rio Vista Energy Partner L.P. 
April 15, 2008