Abstract: The scattered and small-scale production mode, together with asymmetric business information results in the Chinese farmers' weak position in agricultural supply chain. Chinese government has implemented some effective intervention measures, such as minimum price for agricultural products procurement and price subsidy, to safeguard farmer's benefits. By establishing a tripartite evolutionary game model in consideration of price gouging and information asymmetry, the relationship among farmers, dealers of agricultural products and government is analyzed, the boundary of administrative control is also discussed. A case study is given to demonstrate the interrelationships among action, evolutionary path and evolutionary stable strategy(ESS) in the end. The results show that the government would take intervention to punish price gouging, when the size of illegal dealers or the number of farmers involved in trading reaches a certain scale; the probability of dealers choosing fraud strategy is affected by two main factors: the strength of government's intervention and the scale of agricultural products in trading, it declines with the increase of the amount of the fines and increase with the deal size of agricultural products; the minimum price system for purchasing agricultural products can't ensure a positive effect, but an unreasonable discount coefficient may destroy the market system. Therefore, it illustrates that taking reasonable and effective intervention measures makes great significance to protect farmers and maintain market order.

Key words: information asymmetry, price subsidy, tripartite evolutionary game, double intervention of government