The invention provides a synchronous compensator mating secondary device testing system and method. According to the invention, a simulation model is established according to a synchronous compensatorprimary system structure; with a DCS monitoring device, an excitation device, an SFC variable frequency starting device and a synchronizing device, a synchronous compensator mating secondary device testing system is built to comprehensively detect related functions of a protection device, the DCS monitoring device, the excitation device, the SFC variable frequency starting device and the synchronizing device.