Mr. Alex Black reports

RIO ALTO PRODUCES 56,000 OUNCES OF GOLD IN Q1 2012

Rio Alto Mining Ltd.'s La Arena gold mine poured 55,973 ounces of gold during the three months ended March 31, 2012. Sales of 55,327 ounces at an average realized price per ounce of $1,664 generated cash proceeds of $91.4-million. The mine site cash cost per ounce of gold produced was $439. Total cash cost per ounce including corporate overhead and estimates for mining tax, government royalty and workers' profit participation was $651. Cash on hand at the end of March was $70.8-million, an increase during the quarter of $44.9-million.

                    LA ARENA GOLD MINE'S PRODUCTION
                  Three months ended March 31, 2012

                   Actual              Mine plan            Difference      
                Tonnes    Au g/t     Tonnes     Au g/t     Tonnes      Grade
                                                                            
Ore mined    1,289,483      1.37  2,160,000       0.69   (870,517)      0.68
Ore from                                                                    
(to)                                                                       
stockpile      338,395      0.84          -          -    338,395       0.84
Ore placed                                                                  
on pad       1,627,878      1.26  2,160,000       0.69   (532,122)      0.57
Ounces                                                                      
placed on                                                                  
pad                       66,091                48,126                17,965
Waste mined  2,262,038       n/a  1,568,037        n/a    694,001        n/a
Waste-to-                                                                    
ore ratio         1.39       n/a       0.73        n/a       0.66        n/a
                                                                            
            Production     Ounce                                            
             variances variances                                            
Ore placed                                                                  
on pad                                                                     
difference    (532,122)  (11,856)                                           
Ore grade                                                                   
difference        0.57    29,821                                            
                          ------                                            
Ounce variance            17,965                                            

Ore grade mined continues to be significantly higher than predicted by the mine block model. The model projected a weighted average grade of 0.69 gram per tonne gold for the quarter; whereas, ore mined assayed 1.37 g/t Au. Due to this positive grade reconciliation and unusually heavy rains during the period, which slowed leach pad expansion, mining efforts were directed to waste removal. Ore tonnes mined were approximately 871,000 tonnes less than plan and waste removal exceeded plan by 694,000 tonnes. The current leach pad expansion program was completed in April and there is sufficient capacity for the next quarter.

            MINE SITE CASH COST PER OUNCE AND 
              TOTAL COST PER OUNCE PRODUCED

                                  ($000s)   $ per ounce

Mine site costs                  $24,583           $439
Lima office                          876             16
Vancouver office                     674             12
Mining tax and royalty             5,763            103
Workers' profit share              4,575             82
                                 -------           ----
Total costs                      $36,471           $652
                                 =======           ====

Management expects that the La Arena gold mine will produce 150,000 to 160,000 ounces of gold at a mine site cash cost of approximately $500 to $550 per ounce and total cash cost of $600 to $650 per ounce for the year ended Dec. 31, 2012.

With a proven technical team, strong operating and financial performance, and high-quality development and exploration projects, Rio Alto is positioned to grow into an intermediate gold producer from existing projects. Based on current plans and assumptions the company projects gold oxide production of over 200,000 ounces per year by 2014. All planned development, exploration and capital expenditures for 2012 will be completed without external financing and the company should end the year in a stronger financial position. Rio Alto plans to pursue accretive acquisitions and carry out the company's planned exploration programs.

We seek Safe Harbor.