Integrated simulation can be used to test the correctness and reliability of unmanned aerial vehicle (UAV) system, which can reduce the risk effectively in UAV flight. An Integrated simulation method of UAV is proposed in this paper. Based on UAV wind tunnel data and MATLAB, simulation model is built and real-time simulation system is developed. Simulation cable is designed according to the hardware interface and integrated simulation platform is constructed. Simulation and analysis are finished based on a type of UAV. The re-sults between simulation and flight data are the same, which shows that the integrated simulation system has high confidence and simulation method is right. After simulation, the system can be verified and flight risk can be reduced.