OSISKO FILES TECHNICAL REPORT FOR UPDATED WINDFALL MINERAL RESOURCE ESTIMATE

TORONTO, April 03, 2020 (GLOBE NEWSWIRE) -- Osisko Mining Inc. (OSK:TSX, "Osisko" or the "Corporation") is pleased to announce that it has filed a technical report in accordance with National Instrument 43-101 – Standards of Disclosure for Mineral Projects to update the mineral resource estimate on its 100% owned Windfall gold deposit. The technical report entitled "An updated mineral resource estimate for the Windfall Lake Project, Located in the Abitibi Greenstone Belt, Urban Township, Eeyou Istchee James Bay, Québec, Canada" and dated April 3, 2020 (effective date of January 3, 2020) has been prepared for Osisko by Micon International Limited and BBA Inc. The technical report is available on SEDAR (www.sedar.com) under Osisko's issuer profile.

About Osisko Mining Inc.
Osisko is a mineral exploration company focused on the acquisition, exploration, and development of precious metal resource properties in Canada. Osisko holds a 100% interest in the high-grade Windfall gold deposit located between Val-d'Or and Chibougamau in Québec and holds a 100% undivided interest in a large area of claims in the surrounding Urban Barry area and nearby Quévillon area (over 2,700 square kilometres).

Cautionary Statements Regarding Mineral Resource Estimate
Readers are cautioned that mineral resources are not mineral reserves and that the economic viability of mineral resources that are not mineral reserves has not been demonstrated. The mineral resource estimate described in this news release may be materially affected by geology, environmental, permitting, legal, title, socio-political, marketing or other relevant issues. The mineral resource estimate is classified in accordance with the Canadian Institute of Mining, Metallurgy and Petroleum's "CIM Definition Standards on Mineral Resources and Mineral Reserves" incorporated by reference into National Instrument 43-101 – Standards of Disclosure for Mineral Projects ("NI 43-101"). Readers are cautioned not to assume that further work on the stated mineral resources will lead to mineral reserves that can be mined economically.

CONTACT INFORMATION:
John Burzynski
President & Chief Executive Officer
Telephone (416) 363-8653