The working principle of solenoid ball valve was analyzed to establish the corresponding power bond graph. Dynamic performance curves and the structural parameters affected about the solenoid ball valve were achieved by using the 20-Sim software for modeling analysis. The results show that the designed solenoid ball valve has fast response time, small overshoot and large working range, and the maximum output flow rate is 12 L/min. In addition, the size of the orifice in the balancing loop, the spool stroke and the spring stiffness have great impact on the solenoid pushing force, the outlet flow and the life of the valve respectively.