Compared with regular mechanical operating mechanisms, the hydraulic operating mechanism has widespread industrial applications in large hydraulic systems such as ultra-high voltage circuit breakers due to its requirements of fast response, high flow rate and instantaneous super power. This paper intends to analyze the characteristics of hydraulic operating mechanism for ultra-high voltage circuit breakers from a systemic perspective. A comprehensive mathematical model of hydraulic operating mechanism system including pipelines and all valves has been developed. Meanwhile, experiments focusing on the dynamic and pressure characteristics of hydraulic operating mechanism are conducted to validate simulation models. The proposed research methods can provide significant theoretical guidance and practical value for further study of hydraulic operating mechanism of high standard hydraulic system like ultra-high voltage circuit breakers.