To study the dynamic response characteristics of a high-speed on-off valve and optimize its parameters,the structure and working principle of the on-off valve were described and its mathematical model was established.Based on the finite element model of solenoid electromagnet,the role of magnetic shunt at the mouth of pole shoe was studied emphatically,and then the discrete spatial distribution of electromagnetic force and magnetic flux was obtained.With the results of finite element analysis,the mechanic-electronic- hydraulic co-simulation model of on-off valve was established,then the static pressure control characteristics and dynamic response of the key parameters were studied.Based on the results of univariate analysis,the (1+1)-ES algorithm was applied to perform the parameter optimization process.Finally,the dynamic response characteristics of high-speed on-off valve were measured,the comparative verification was completed.The experimental results show that the established simulation model describes the dynamic response characteristics of on-off valve well,and its performance is effectively improved by evolution strategy optimization algorithm.