Denison Announces Filing of Annual Report on Form 40-F

TORONTO, March 28, 2018 -- Denison Mines Corp. (“Denison” or the “Company”) (TSX:DML) (NYSE American:DNN) is pleased to announce that it has filed its 2017 annual report on Form 40-F with the U.S. Securities and Exchange Commission ("SEC").  Denison’s Form 40-F incorporates by reference the management discussion and analysis and audited financial statements of the Corporation for the year ended December 31, 2017, as furnished to the Commission on Denison’s Form 6-K dated March 9, 2018. Denison's Form 40-F is available on Denison's website at www.denisonmines.com, and on the SEC's website at www.sec.gov/edgar.shtml.

In addition, Denison has filed its Annual Information Form with Canadian regulatory authorities, which is also available on Denison's website at www.denisonmines.com and under the Company's profile on SEDAR at www.sedar.com.

Holders of Denison's securities may receive a free printed copy of the Company's most recent Form 40-F and Annual Report, including the audited financial statements, by sending an email request to [email protected], by submitting a request online at www.denisonmines.com, or by writing to Denison Mines Corp., 1100 - 40 University Avenue, Toronto, Ontario, Canada M5J 1T1.

About Denison

Denison is a uranium exploration and development company with interests focused in the Athabasca Basin region of northern Saskatchewan, Canada. In addition to its 63.3% owned Wheeler River project, which hosts the high-grade Phoenix and Gryphon uranium deposits, Denison's exploration portfolio consists of numerous projects covering approximately 351,000 hectares in the Athabasca Basin region, including approximately 316,000 hectares in the infrastructure rich eastern portion of the Athabasca Basin. Denison's interests in Saskatchewan also include a 22.5% ownership interest in the McClean Lake joint venture (“MLJV”), which includes several uranium deposits and the McClean Lake uranium mill, which is currently processing ore from the Cigar Lake mine under a toll milling agreement, plus a 25.17% interest in the Midwest and Midwest A deposits, and a 64.22% interest in the J Zone deposit and Huskie discovery on the Waterbury Lake property. Each of Midwest, Midwest A, J Zone and Huskie are located within 20 kilometres of the McClean Lake mill.

Denison is also engaged in mine decommissioning, environmental and other consulting services through its Denison Environmental Services division and is the manager of Uranium Participation Corp., a publicly traded company which invests in uranium oxide and uranium hexafluoride.

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