Considering the hydraulic impact of broken belt catch system,the original whole section wedge broken belt catch device was imprved by introducting the relief valve.The working principle of the whole broken belt catch hudraulic system was describe.The simulation model of the improved broken belt catch hudraulic system was established,simulated and analyzed based on the AMESim software.After simulation,the dynamic response curves of the cylinder piston speed and displacement when the wedge broken belt catch system was under the catching situation were obtained.The results show that the cylinder piston starts decelerating on the half stroke of cylinder by setting the relief valve on the rod cavity of cylinder,the speed of cylinder piston is 0 when the displacement is 3.0 m and the improved broken belt catch hydraulic system can reduce the hydraulic impact at the end of the cylinder.