The Fuzzy—PID complex technology was adopted to solve the control technical problem of air suspension. The fuzzy reasoning was applied to the self-tuning of PID parameters, and the research was conducted on semi-active air suspension. A Fuzzy—PID controller was designed, which was used in Matlab/Simulink simulation and bench test of 1/4 model of the semi-active air suspension. A Fuzzy—PID module was constructed with S function and Fuzzy Inference System Toolbox in the simulation model. Compared with the traditional PID control, the control of the semi-active air suspension could be used to reduce the sprung mass acceleration and suspension action itinerary with better robustness advantages, and improve ride comfort. The simulated results agreed well with the testing data. 