RIO Rio2 Limited New

Rio Alto Mining Limited ("Rio Alto" or the "Company") (TSX VENTURE: RIO)(BVLAC: RIO)(FRANKFURT: MS2)(A0MSLE) reports that it has closed the previously announced minimum $3 million private placement of its common shares (the "Shares") at $0.36 per Share. Kallpa Securities S.A.B. ("Kallpa SAB") acted as the agent for the private placement. The offering was subscribed to by Peruvian investors and the gross proceeds of the placement amounted to US$5.776 million ($6.136 million).

Feisal Somji, Director and CEO commented that "We expected knowledgeable Peruvian mining investors to take the opportunity to participate in this offering. What we didn't fully anticipate was the overwhelming demand, which is a positive endorsement for the quality of the La Arena Project and the Company's local management. It is also a reflection of the effort made by Kallpa SAB. The proceeds of this placement will allow us to maintain the development schedule for the La Arena gold oxide mine."

Upon receipt of all necessary approvals, the Company will issue 17,044,927 Shares to qualified investors and pay a cash fee of $398,850 to Kallpa SAB. Net proceeds of the offering will be used by the Company for development of the La Arena Gold Oxide Project and for general corporate purposes. The Shares issued pursuant to the private placement are subject to a statutory resale restriction period of four months and a day expiring on April 1, 2010. The completion of the private placement is subject to final approval from the TSX Venture Exchange.

Rio Alto plans to bring the La Arena Gold Oxide Project, in Peru, into production during 2010 and to use cash flow from production to further develop its assets in Peru and Mexico. To learn more about Rio Alto Mining Limited, please visit: www.rioaltomining.com. Financial information and other information can also be found at the Company's profile at www.sedar.com.

ON BEHALF OF THE BOARD OF RIO ALTO MINING LIMITED

Anthony Hawkshaw, Director and Chief Financial Officer

Forward Looking Statements

Certain statements contained herein constitute forward-looking statements, including the use of proceeds of the private placement and development of the La Arena Gold Oxide Project. Rio Alto believes the expectations reflected in these forward looking statements are reasonable but no assurance can be given that these expectations will prove to be correct and such forward-looking statements in this press release should not be unduly relied upon. Forward-looking statements included in this press release are made as of the date of this press release and Rio Alto disclaims any intention or obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise, except as expressly required by applicable securities legislation.

Neither the TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this release.

Contacts: Rio Alto Mining Limited Anthony Hawkshaw 778.995.1137 604.943.5364 (FAX) tonyh@rioaltomining.com Rio Alto Mining Limited Alejandra Gomez Investor Relations 604.762.8918 604.943.5364 (FAX) alejandrag@rioaltomining.com www.rioaltomining.com