Exhibit 32.1

Certification of Principal Executive Officer

Pursuant to 18 U.S.C. § 1350,

As Adopted Pursuant to

Section 906 of the Sarbanes-Oxley Act of 2002

In connection with the Quarterly Report of Reef Global Energy IV, L.P. (the “Partnership”) on Form 10-Q for the quarter ended June 30, 2010 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I, Michael J. Mauceli, principal executive officer of the Partnership, certify, 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 Partnership.

Date: August 13, 2010

	/s/ Michael J. Mauceli
	Michael J. Mauceli
	Manager and Member of Reef Oil & Gas Partners,
	GP, LLC, the manager of Reef Oil & Gas Partners,
	L.P., the Managing General Partner of the
	Partnership
	(Principal Executive Officer)

This certification accompanies the Report pursuant to § 906 of the Sarbanes-Oxley Act of 2002 and shall not, except to the extent required by the Sarbanes-Oxley Act of 2002, be deemed filed by the Partnership for purposes of § 18 of the Securities Exchange Act of 1934, as amended.

A signed original of this written statement has been provided to the Partnership and will be retained by the Partnership and furnished to the Securities and Exchange Commission or its staff upon request.

Reef Global Energy IV, L.P. 10-Q