Abstract: Objective The industrial application field has put forward higher requirements for the performance of complex stainless steel components, in order to improve the microstructure uniformity and mechanical properties of 316L stainless steel. Methods In this paper, 316L austenitic stainless steel was prepared by laser melting deposition (LMD). The microstructure evolution and mechanical properties of different deposition strategies were studied. Results The experimental results show that the microstructure of 316L austenitic stainless steel prepared by LMD is mainly composed of a large number of coarse columnar crystals and a small amount of irregular equiaxed crystals. The grain size and substructure size of R90 sample are the smallest. The comprehensive comparison shows that R90 sample has the best comprehensive mechanical properties. The yield strength and ultimate tensile strength are 484.0 MPa and 627.6 MPa, the elongation is 35.9 %. The substructure of 316 stainless steel prepared by laser additive has the same fine-grained strengthening effect as high angle grain boundaries (HAGBs). Conclusion It provides the optimal process for enhancing the microstructure and mechanical properties of additive manufacturing 316L stainless steel, broadening the application fields of stainless steel.