Based on the annual data of China’s nine corn main producing provinces between 2001 and 2014,this paper employs three performance evaluation models of corn reserve policy by means of DID,Class DID and Propensity Score Matching methods to eliminate other affecting factors on corn prices.In addition,this paper uses panel data PoolOLS to test the independent effects on corn reserve policy in China.the estimations of DID and Class DID methods show that in the provinces implementing corn reserve policy,this policy significantly raises the prices of corn,with margin of 0.14 yuan/kg and 0.17 yuan/kg,respectively.Compared with the average price of sampling provinces,the growth rates are 9.26% and 11.88%,respectively,and the supporting effect on corn prices is obvious.The result of PSM reveals that the backup effect of reserve policy on corn prices is 0.15 yuan/kg,which verifies the robustness of DID and Class DID methods.