“Connecting Farmers and Supermarkets” model is considered to be an important way to solve the problem of increasing farmer's income and the inefficient circulation of agricultural products. However, the farmer's opportunistic behavior occurs frequently. Therefore, this study believes that farmer's psychological contract could affect the opportunistic behavior and the organizational commitment of farmers plays a mediating role. This paper constructs a complete information static game theory model, which verifies that only by establishing a long-term cooperation mechanism, concluding an ideal relationship psychological contract, or making farmers form a strong commitment to the supermarket, can they get out of the dilemma of one-off game, trigger the long-term cooperation strategy with supermarkets. It also puts forward policy suggestions to restrain the farmer's opportunistic behavior in mode of "Connecting Farmers and Supermarkets"