The free manufacture from powders to parts can be realized by the technique of selective laser melting (SLM), and the formed parts have a high size accuracy and a low surface roughness. SLM is especially suitable for the formation of the moulds with complex structures. The research status of SLM and forming of mould steels as well as their molding materials, process characteristics, microstructure evolution and performance optimization are mainly summarized. The application status such as the application of conformal cooling channels is briefly described. The existing problems in the SLM and forming of mould steels are summarized and the future research direction is prospected and discussed.