Denison Announces Filing of Annual Report ON Form 40-F

Denison Mines Corp.

1100 – 40 University Ave

Toronto, ON M5J 1T1

www.denisonmines.com

@DenisonMinesCo

PRESS RELEASE

DENISON ANNOUNCES FILING OF ANNUAL REPORT ON FORM 40-F

Toronto, ON – March 28, 2018 Denison Mines Corp. (“Denison” or the “Company”) (DML: TSX; DNN:

NYSE American) 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"). Deniso n’s Form 40-F incorporates by reference the

management discussion and analysis and audited fina ncial statements of the Corporation for the year

ended December 31, 2017, as furnished to the Commis sion on Denison’s Form 6-K dated March 9, 2018.

Denison's Form 40-F is available on Denison's websi te at www.denisonmines.com, and on the SEC's

website at www.sec.gov/edgar.shtml.

In addition, Denison has filed its Annual Informati on Form with Canadian regulatory authorities, which is

also available on Denison's website at www.denisonm ines.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 onli ne 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 additio n to its 63.3% owned Wheeler River project, which

hosts the high-grade Phoenix and Gryphon uranium de posits, Denison's exploration portfolio consists of

numerous projects covering approximately 351,000 he ctares 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% owne rship interest in the McClean Lake joint venture

(“MLJV”), which includes several uranium deposits and the McClean Lake uranium mill, which is currentl y

processing ore from the Cigar Lake mine under a tol l 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, en vironmental and other consulting services through

its Denison Environmental Services division and is the manager of Uranium Participation Corp., a publi cly

traded company which invests in uranium oxide and uranium hexafluoride.

For more information, please contact

David Cates (416) 979 -1991 ext. 362

President and Chief Executive Officer

Sophia Shane (604) 689 -7842

Investor Relations

Follow Denison on Twitter @DenisonMinesCo