Abstract: The rod size and closing spring parameters of the four-bar mechanism in the vacuum circuit breaker spring operating mechanism have a direct effect on the closing speed and displacement characteristics of the moving contact,including stroke bounce and mechanism wear. This paper takes the spring operating mechanism for10 kV circuit breaker as the object,uses SolidWorks software to establish the 3D model of the motion system,and introduces the dynamic simulation software ADAMS to analyze the motion characteristics of the 3 D model. Under the condition of keeping the opening energy storage level and the opening spring compression constant,the size of connecting rod and link and the pre-tightening force of closing spring are taken as optimization variables,the objective is to minimize the maximum instantaneous speed of moving contact and the minimum sum of relative rod length,the multi-parameter and multi-objective optimization design of the mechanism is carried out by using DOE parametric analysis method,in order to control the mechanism output characteristic.