Abstract: To solve the problem of transversal turnover of the paddy field boat during the cultivation operation, combining the method of theoretical calculation with paddy field test, the kinetic and dynamic characteristics were analyzed and the mathematical model was established according to movement stability in this paper. Through analyzing and calculating, the relationship expression of the minimum turning radius based on this model was concluded. Applying this theory to 1BG-0.9 paddy field boat with bottom plow, the minimum turning radius was figured out. The minimum turning radius and the maximum turning angle were determined through paddy field testing and the stability was ensured. This study provided theoretical basis for designing and developing this kind of machine.