To analyze the willingness to cooperate of farmers to participate in water management, we base on game theory and first carry on single static game analysis of willingness to cooperate for farmers to participate in water management, and find that farmers are into a Prisoners Dilemma in a single game, individual rationality comes into conflict with collective rationality, at this time farmers have a tendency to "free riders", so it is difficult to achieve cooperation between the farmers. Then trying to break the prisoners' dilemma, we carry on the farmers repeated dynamic game, the analysis is carried on in the context of incomplete information and limited rationality, we carry on game evolution analysis for willingness to cooperate for farmers to participate in water management. In order to guarantee the rationality of the study, we conduct a survey of willingness to cooperate of farmers to participate in water management in province of Zhejiang and finally confirm that the study is reasonable. And through the analysis of the full text, we conclude six important conclusions.