Fuzzy-PID control is used in the Variable rate fertilization controlling system and the rule of the fuzzy control is determined. Based on the dynamic model of the Variable rate fertilization controlling system, MATLAB/Simulink is applied to simulate the torque and the rotation speed of the engine. The experimental results indicate that the proposed method is of simple arithmetic and real-time characteristics and has good robustness and fast response for field operation of variable fertilization seeder.