Based on the electrohydraulic ratio control technology,a crawler chassis hydraulic drive system was designed to realize the linear and steering control.On the basis of the control principle and the chassis kinematics,the relationship between the steering angle and the track speed of the motors was deduced.To improve the dynamic response performance of the system,the PID controller and the fuzzy PID control strategy were designed.The simulation model was established based on AMESim and MATLAB/Simulink and joint simulation study was performed.The results show that using the control strategy,when the chassis is running in a straight line，synchronization control effect of the motor on both sides is good,with good anti-interference ability and small overshoot;when the chassis turns,the tracking error to the given signal is small with fast response speed,small overshoot and good robustness.