The air compressor system is a time-varying, delay and nonlinear complex system, it has a very important sense to ensure that the supply pressure is stable in the compressor control system. According to the working characteristic of air compressor system, the fuzzy control theory, as one of the modern control theories, was applied into the constant pressure control system to design a fuzzy pressure controller. The simulation results show that the controller was more convenient and effective; it has certain directive significance and reference for the other parameter’s control of air compressor system.