Abstract: The impact resistance is an important indicator for the ship equipment. In this article, the three-dimensional model of a device's cantilever structure is established by using UG, and the impact input spectrum is converted into an acceleration-time history curve by using the positive and negative triangular waves. The finite element analysis on impact resistance of the cantilever structure is conducted with the time-domain analysis method. Based on the obtained analysis results, the weak parts on the cantilever structure are optimized for design; then the simulation analysis is conducted on the optimized model, and the feasibility of optimization is thus demonstrated. It provides reference suggestions for the subsequent impact resistance design of cantilever structures.