The development background and technical characteristics of in-space manufacturing technologies are analyzed in this paper. Some research progresses in in-space additive manufacturing and welding technologies are introduced， and the research hotspots in related fields are summarized. It includes the development status of in-space additive manufacturing technologies and equipments of nonmetal and metal materials， and the research progress of in-space welding technologies and equipments， such as electron beam welding， solid state welding and so on. The developing direction of in-space manufacturing technology in China is discussed. The research results can provide reference for the future research and development of in-space manufacturing technology in China.