In order to analyze the hydraulic system of the concrete pump trucks arm, it is necessary to model and simulate the load sensitive proportional multiway valve of the key components of the hydraulic system. Its dynamic characteristics were analyzed and obtained. According to the working principle of the load sensitive proportional multiway valve used in the hydraulic system, through multidisciplinary modeling, simulation, analysis software SimulationX, simulation model of the valve was established, and dynamic simulation was carried out. The results indicate that this valve is in accordance with practical operating conditions, and modeling method is simple.