In order to train the capability of unmanned aerial vehicle (UAV) operators to deal with the fault, and verify the effectiveness of the fault detection and processing scheme, a UAV fault injection simulation system is designed. Based on the advanced distributed architecture, the system performs real-time simulation and has good scalability. Wide coverage of fault scenarios could reappear by the distributed closed-loop simulation system. This system ensures the accuracy of the simulation results and meanwhile provides an intuitive feeling in the visual display module. The application results show that the simulation system has good real-time performance, high fidelity, and immersion. It provides effective support for verifying the processing ability of the UAV system to deal with faults and the rationality of the emergency response plan.