Abstract: The article analyzes the influence of impact load on the stability of lower slide of slitting machine in order to improve its working performance. The deformation and stress of the lower slide under the static load are analyzed by statics simulation, and the response spectrum is simulated by using the mass-spring system to convert the velocity signal into acceleration response spectrum. The dynamic and static simulation results are combined to analyze the influence of impact load. After the optimization design, the deflection of the tool shaft under the impact load is reduced from 40.13 μm to 28.86 μm, which decreases by 16.73%, which helps to improve the stability and production efficiency of the slitting machine. The optimized slitting machine works well and the simulation results are verified.