Abstract: The establishment of rural land bank was necessary for ensuring national food security,developing modern agriculture and establishing long-term mechanism to increase farmer's income. It was also a significant changes in rural china to achieve strategic move.This paper based on food security and use Land Bank as research perspective, and the dynamic game model of contingent play, mainly to solve the minimum operation scale that operators need to maintain and the planting ratio of food crops and cash crops, and also make appropriate policy recommendations.