In order to investigate dimensional accuracy of geometric features manufactured by selective laser melting (SLM) and to provide design references for SLM to manufacture metal parts directly, several typical geometric features such as thin walls, sharp corners, cylinders, circular holes, square holes, etc are designed. Then SLM equipment DiMetal-100 is employed and 316L stainless steel powders are used to manufacture these typical geometric features under the condition of optimized process parameters. It is shown that laser spot restraint, step effect, powder adhesion and laser deep penetration are the main factors which affect dimensional accuracy of parts and affect manufacturing ability of SLM. The manufacturing ability of SLM and the dimensional accuracy of typical geometric features by SLM is studied. It puts forward some preliminary design rules suitable for SLM, which provides a reference for innovative design of products.