The drilling rig does not run smoothly because of serious hydraulic shock when the hoisting system starts and closes. The main reason of hydraulic shock is that when the reversing valve is opened and closed, the kinetic energy of hydraulic oil and load is converted into pressure energy instantly. In this paper, the impact of hydraulic shock is reduced by improving the circuit of the hoisting hydraulic system and selecting a reasonable lifting speed. Theoretical and AMESim modeling and simulation of the hoisting hydraulic system befero and after improvement indicates that the improved hydraulic system has obvious control over hydraulic shock, and the system stability is greatly improved. After reforming the hoisting system of the drilling rig, hydraulic shock disappeared during stepping up, and vibration of the drilling rig was greatly reduced with stability enhanced.