FORM 6-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Report of Foreign Private Issuer

Pursuant to Rule 13a-16 or 15d-16 of

the Securities Exchange Act of 1934

Date: May 23, 2013

Commission File Number: 001-33414

Denison Mines Corp.

(Translation of registrant’s name into English)

Atrium on Bay, 595 Bay Street, Suite 402, Toronto, Ontario M5G 2C2

(Address of principal executive offices)

Indicate by check mark whether the registrant files or will file annual reports under cover Form 20-F or Form 40-F.

Form 20-F  ¨            Form 40-F  x

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1):  ¨

Note: Regulation S-T Rule 101(b)(1) only permits the submission in paper of a Form 6-K if submitted solely to provide an attached annual report to security holders.

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7):  ¨

Note: Regulation S-T Rule 101(b)(7) only permits the submission in paper of a Form 6-K if submitted to furnish a report or other document that the registrant foreign private issuer must furnish and make public under the laws of the jurisdiction in which the registrant is incorporated, domiciled or legally organized (the registrant’s “home country”), or under the rules of the home country exchange on which the registrant’s securities are traded, as long as the report or other document is not a press release, is not required to be and has not been distributed to the registrant’s security holders, and, if discussing a material event, has already been the subject of a Form 6-K submission or other Commission filing on EDGAR.

Indicate by check mark whether by furnishing the information contained in this Form, the registrant is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.

Yes  ¨             No  x

If “Yes” is marked, indicate below the file number assigned to the registrant in connection with Rule 12g3-2(b): 82-                     

Signatures

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

	Denison Mines Corp.
		/s/ Sheila Colman
		Sheila Colman
Date: May 23, 2013		Corporate Counsel and Corporate Secretary

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EXHIBIT INDEX

Exhibit Number	Description
1.	Press Release dated April 26, 2013
2.	Press Release dated May 8, 2013
3.	Management’s Discussion and Analysis for the period ended March 31, 2013
4.	Financial Statements for the period ended March 31, 2013
5.	Certification of Interim Filings—CEO
6.	Certification of Interim Filings—CFO
7.	Press Release dated May 9, 2013
8.	Press Release dated May 10, 2013
9.	Report of Voting Results

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