The utility model discloses a testing device for a power module of a chain type static synchronous compensator, which comprises a first single-phase isolation transformer TR1, a second single-phase isolation transformer TR2, a first alternating-current switch K1, a second alternating-current switch K2, a contactor J1, a rectifier bridge B1, an analog controller C1, a current limiting resistor R1, a discharging resistor R2 and a fuse F1. The utility model has the advantages that the testing device has low cost, is easy to carry and use, and is suitable for onsite testing of the power module of the chain type static synchronous compensator.