According to the basic functions and main technical characteristics of a certain airborne avionics equipment, a test system is designed. The overall design, hardware and software of the test system are described. The hardware design is critical to realize the function of the test system. The function modules of excitation signal generation, fault information injection and data acquisition are discussed in detail. The classification and work flow of the software function modules are described. The test system has been applied to the debug, delivery acceptance and troubleshooting of the airborne avionics equipment. It shows that the test system has the reasonable design software and hardware, high automation, stable and reliable work in application, which improves the test efficiency and saves the human resource.