In order to improve the forming quality of medical Ti6Al4V titanium alloys by selective laser melting (SLM), the process parameters of laser partition scanning are optimized. By the orthogonal experiment and single factor experiment, the microstructure characteristic, efficiency of space filling, dimensional accuracy and surface quality of formed parts under the partition scanning strategy and the traditional overall scanning strategy are compared and analyzed. The typical surface morphologies of medical Ti6Al4V titanium alloys formed by SLM are summarized. The research results show that the partition scanning strategy can not only increase the dimensional accuracy and surface quality of titanium alloys, but also significantly improve the forming effect of overhanging surfaces.