Abstract: To study the influence of movement trend,mechanical state and shield beam structure after the shield beam under impact load,the paper uses a multi-body dynamics software ADAMS to establish the numerical sim-ulation mod- el of hydraulic support. In the model,the shield beam is set as flexible by pre-processing software Hypermesh,the leg and balance jack are replaced by the spring damping system equivalently,the stiffness of the leg is set as the variable stiffness,initial support force is provided by the preload of the equivalent spring,roof pressure is applied vertically to roof through a static load,the impact load caused by immediate roof and main roof rock falls on the shield beam is re- placed by the step load. Based on the above model,the paper analyzes the horizontal forward displacement of canopy, the contact force variations between canopy and roof,the force variation of each hinge joint and shield beam stress change when the impact load acts on the different positions of the shield beam. The results show that the different posi- tion of load caused the different various trends of hydraulic support. This is of great significance for the stability control and equal strength design of hydraulic support.