When the circuit breaker of the hydraulic operating mechanism is in normal operation, its pressure value will drop. If the pressure value drops, the pressing motor can not press normally because of external factors to restore the pressure value to the rated value, if it is not found and treated in time, the pressure will be further reduced, resulting in the closure of the switch, causing great harm to people, power grid and equipment. Based on the practical work, the hydraulic low-monitoring circuit of the circuit breaker of the hydraulic operating mechanism is designed and perfected, and the pressure value of the circuit breaker is effectively monitored to ensure the reliability and stability of the operation of the hydraulic circuit breaker, the paper provides a reference for the prevention and solution of the accident.