With the improvement of the living standards of the people in the country, cars play an increasingly important role in people’s lives. The manual control of the car air conditioner distracts the driver’s attention and the cabin temperature does not meet the requirements of comfort and energy saving. In this paper, MATLAB/Simulink is used to establish the electric vehicle air-conditioning model and fuzzy PID controller model, and the joint simulation research of vehicle interior temperature control is carried out. The co-simulation model is used to compare the air conditioning performance with fuzzy PID control and PID control. The results show that with fuzzy PID control, the temperature fluctuation inside the car is small and the overshoot is small.