Abstract: For research on the control target of vehicle handling stability, the cut-off point of the positive steering and reverse steering of the low-speed and high-speed rear wheels of the car with rear steer is obtained.The calculation methods of proportional control and yaw rate feedback tracking control are derived.According to the dynamic equation of two degrees of freedom of the vehicle, the establishment of the ideal target object is solved.Through the analysis of feedback error E and variation error EC,the domain range and fuzzy PID controller are designed.Carsim and Simulink are used for joint simulation, the front left wheel is used as the reference input angle, other input angle are obtained by lookup table, and the angular step is used as the evaluation input, and the model established in this paper is simulated and analyzed.The results show that the fuzzy PID controller can make the car significantly better than the front wheel steering and yaw rate feedback tracking control methods at low speed and high speed.It greatly improves the handling performance of the car, giving full play to the advantages of rear-wheel steering providing oversteer at low speed and understeer steering at high speed.