The utility model discloses a circuit breaker parameter testing auxiliary device, including the operational unit who is used for operating means, be used for becoming alternating current 220V voltage conversion the unit of direct current 220V voltage, the input and the external alternating current power supply of voltage conversion unit are connected, and the output is connected with operational unit, an interface unit, the interface unit setting on operational unit that is used for being connected with the circuit breaker test wire. The utility model discloses simple structure, convenient to use, but safe and reliable ground provides operating voltage for the circuit breaker, accomplishes the test to the circuit breaker parameter to its interface unit includes the interface of multiple different models, can realize the simultaneous working of the circuit breaker of different models, has greatly improved work efficiency. The utility model is suitable for a circuit breaker parameter testing for multiple model provides operating voltage.