The influence of laser shock peening (LSP) treatment on the microhardness, residual stress and microstructure of the cladding layer surface of 316L stainless steel is studied. The results show that, the microhardness and residual stress of the cladding layer after LSP are improved obviously; the change of microstructure occurs obviously, and the grains are refined where columnar structures transform to equiaxial structures; the current density of self-corrosion of the cladding layer is reduced, and the corrosion resistance of the material is improved.