Laser shock processing (LSP) has been proposed as a new surface treatment for improving hardness,wear resistance and fatigue. In this paper, the effect of LSP on brass is investigated with experiment. Micro-hardness, roughness, microstructure, wear resistance and friction coefficient evolution are investigated for different parameters of LSP. The result shows that the roughness increases after LSP; no ablation is observed; the microstructure has no remarkable change; hardness and the wear resistance increase as the pulse density increases.