Osisko Announces $12.25 Million Flow-Through Financing

MONTREAL, QUEBEC--(Marketwire - Sept. 19, 2008) - Osisko Mining Corporation (TSX: OSK.TO)(FRANKFURT: EWX.F) is pleased to announce that it has entered into non-brokered financing agreements with three funds to issue up to C$12.25 million in flow-through shares. The private placement will consist of a maximum of 2,916,725 flow-through shares issued at a price of $4.20 per share.

Osisko will pay finder fees of 4% of the gross proceeds of the transaction. The private placement is expected to close on or about September 30, 2008 and is subject to regulatory approvals. The securities issued under this private placement are subject to a four month hold period from the closing date.

Commenting on the transaction, Sean Roosen President and CEO of Osisko stated: "The funds will allow Osisko to continue its aggressive exploration program in the Malartic Camp to help augment the significant resources already identified on the Canadian Malartic Project, while we continue towards our goal of establishing Osisko as a mid-tier Canadian gold producer."

About Osisko

Osisko Mining Corporation is currently evaluating the Canadian Malartic gold deposit and adjacent areas for a large-scale open pit, bulk-tonnage mining operation. The Company is well-funded with approximately $140 million on hand and is carrying out an aggressive definition drilling and exploration campaign on the Canadian Malartic deposit and surrounding properties.

Forward Looking Statements

Certain statements contained in this press release may be deemed "forward-looking statements". All statements in this release, other than statements of historical fact, that address events or developments that the Corporation expects to occur, are forward looking statements. Forward looking statements are statements that are not historical facts and are generally, but not always, identified by the words "expects", "plans", "anticipates", "believes", "intends", "estimates", "projects", "potential", "scheduled" and similar expressions, or that events or conditions "will", "would", "may", "could" or "should" occur. Although the Corporation believes the expectations expressed in such forward-looking statements are based on reasonable assumptions, including, without limitation that all technical, economical and financial conditions will be met in order to put the Canadian Malartic Project into commercial production, such statements are not guarantees of future performance and actual results may differ materially from those in forward looking statements. Factors that could cause the actual results to differ materially from those in forward-looking statements include gold prices, access to skilled consultants, mining development and mill production personnel, results of exploration and development activities, the Corporation's limited experience with production and development stage mining operations, uninsured risks, regulatory changes, defects in title, availability of personnel, materials and equipment, timeliness of government approvals, actual performance of facilities, equipment and processes relative to specifications and expectations, unanticipated environmental impacts on operations market prices, continued availability of capital and financing and general economic, market or business conditions. These factors are discussed in greater detail in the Corporation's most recent Annual Information Form filed on SEDAR, which also provides additional general assumptions in connection with these statements. The Corporation cautions that the foregoing list of important factors is not exhaustive. Investors and others who base themselves on the Corporation's forward-looking statements should carefully consider the above factors as well as the uncertainties they represent and the risk they entail. The Corporation believes that the expectations reflected in those forward-looking statements are reasonable, but no assurance can be given that these expectations will prove to be correct and such forward-looking statements included in this press release should not be unduly relied upon. These statements speak only as of the date of this press release.

Contacts

Vice-President Corporate Development
John Burzynski
514-735-7131
www.osisko.com

Investor Relations
Daniel Boase
416-742-5600
Toll Free: 1-866-580-8891