In a intermittent transonic wind tunnel, it is necessary to control the main exhaust valve while keeping the stagnation constant. In order to improve the control precision and synchronization performance of the main exhaust valve, an accurate mathematical model of the electrohydraulic servo system was built, to eliminate the influence of load disturbance, inner leaks, parameters and device performance difference; based on the virtual axis, masterslaver fuzzy PI control strategy was designed. The simulation results show that the system has high synchronization precision and short adjust time.