Abstract: In order to solve the problems of complex structure, high cost and large maintenance of spring operating mechanism of high voltage circuit breaker, a spring operating mechanism with large output operating power and high stability is studied and designed. The structural strength of the main transmission unit is improved by optimizing the design of the main transmission unit components including cams and output shafts to ensure the stability and reliability of the long-term operation of the high-voltage circuit breaker. The ADAMS software is used to simulate and analyze the motion characteristics of the main transmission unit of the high-power operating mechanism of the high-voltage circuit breaker. The simulation results show that the optimization design of the main transmission unit of the high-power operating mechanism of the high-voltage circuit breaker effectively improves the performance of the high-power operating mechanism of the high-voltage circuit breaker. According to the dynamic characteristic instrument of Wuhan Ocean Circuit Breaker, the opening and closing speed, stroke and other characteristics of the circuit breaker prototype are tested, and the closing and opening characteristic curves are generated. It can be concluded that the opening and closing speed and time of the optimized high-voltage circuit breaker meet the design requirements of the circuit breaker operating mechanism, which can ensure the normal use of the circuit breaker.