Exhibit 99.6

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 Denison Mines Corp. (the “Company”) on Form 40-F 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 certifies, 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.

Date: March 31, 2009

By:	/s/ James R. Anderson		By:	/s/ E. Peter Farmer
	Name:	James R. Anderson		Name:	E. Peter Farmer
	Title:	Exec. V.P. and Chief Financial Officer		Title:	Chief Executive Officer