VANCOUVER, B.C., August 19, 2009 - Augusta Resource Corporation (TSX/NYSE Amex: AZC)

(“Augusta” or “the Company”) has closed the $25 million bought deal financing, announced July 27, 2009, plus a 15% over-allotment option (the “Offering”) exercised in full, for gross proceeds of $28,758,740. The Offering was conducted by a syndicate of underwriters led by Wellington West Capital Markets Inc. and including Cormark Securities Inc., CIBC World Markets Inc. and TD Securities Inc. (collectively the “Underwriters”) for the issuance of 12,380,000 common shares plus 1,857,000 common shares pursuant to the over-allotment option at a price of $2.02 per common share.

In connection with the Offering, the Underwriters were paid a cash commission equal to 5% ($1,437,937) of the gross proceeds of the Offering and compensation options entitling the Underwriters to purchase common shares up to an additional 3% (427,109 common shares) of the Offering at a price of $2.19 per share exercisable in whole or in part until August 6, 2010.

The net proceeds of the Offering will be used to advance the development of the Rosemont Copper property located in Pima County, Arizona and for general working capital purposes.

About Augusta

Augusta is a base metals company focused on advancing the Rosemont Copper deposit near Tucson, Arizona. Rosemont currently hosts a large copper/molybdenum reserve that may account for about 10% of US copper output once in production in late 2011 (for details refer to www.augustaresource.com). The exceptional experience and strength of Augusta’s management team, combined with the developed infrastructure and robust economics of the Rosemont project, will propel Augusta to become a solid mid-tier copper producer by 2012. The Company is traded on the Toronto Stock Exchange and the NYSE Amex under the symbol AZC, and on the Frankfurt Stock Exchange under the symbol A5R.

For additional information please visit www.augustaresource.com or contact:

Meghan Brown

Investor Relations Manager

tel: 604 638 2002

email: mbrown@augustaresource.com

All amounts in this press release are in Canadian dollars.

CAUTIONARY STATEMENTS REGARDING FORWARD LOOKING INFORMATION

Certain of the statements made and information contained herein may contain forward-looking statements within the meaning of the United States Private Securities Litigation Reform Act of 1995 and forward-looking information within the meaning of applicable Canadian securities laws. Such forward-looking statements and forward-looking information include, but are not limited to statements concerning: the Company’s plans at the Rosemont Project; estimated production; and capital and operating and cash flow estimates. Forward-looking statements or information include statements regarding the expectations and beliefs of management. Often, but not always, forward-looking statements and forward-looking information can be identified by the use of words such as “plans”, “expects”, “is expected”, “budget”, “scheduled”, “estimates”, “forecasts”, “intends”, “anticipates”, or “believes” or the negatives thereof or variations of such words and phrases or statements that certain actions, events or results “may”, “could”, “would”, “might” or “will” be taken, occur or be achieved. Forward-looking statements or information include, but are not limited to, statements or information with respect to known or unknown risks, uncertainties and other factors which may cause the actual results, performance or achievements of the Company, or industry results, to be materially different from any future results, performance or achievements expressed or implied by such forward-looking statements or information.

Forward-looking statements or information are subject to a variety of risks and uncertainties which could cause actual events or results to differ from those reflected in the forward-looking statements or information, including, without limitation, risks and uncertainties relating to: history of losses; requirements for additional capital; dilution; loss of its material properties; interest rates increase; global economy; no history of production; speculative nature of exploration activities; periodic interruptions to exploration, development and mining activities; environmental hazards and liability; industrial accidents;failure of processing and mining equipment; labour disputes; supply problems; commodity price fluctuations; uncertainty of production and cost estimates; the interpretation of drill results and the estimation of mineral resources and reserves; legal and regulatory proceedings and community actions; title matters; regulatory restrictions; permitting and licensing; volatility of the market price of Common Shares; insurance; competition; hedging activities; currency fluctuations; loss of key employees; as well as those factors discussed in the section entitled “Risk Factors” in the Company’s prospectus dated August 17, 2009 . Should one or more of these risks and uncertainties materialize, or should underlying assumptions prove incorrect, actual results may vary materially from those described in forward-looking statements or information. Accordingly, readers are advised not to place undue reliance on forward-looking statements or information. The Company disclaims any intent or obligation to update forward-looking statements or information except as required by law, and you are referred to the full discussion of the Company’s business contained in the Company’s reports filed with the securities regulatory authorities in Canada and the United States..