Compared with the traditional metal tank, the space composite cryotank can achieve weight reductions up to 20%–40%, which provides the possibility for the research and development of the next generation of low-cost, highcapacity and recoverable spacecraft. The inevitability of the development of space composite cryotank is systematically analyzed. Furthermore, the achievements and problems in this field in developed countries during recent 30 years are introduced from the aspects of demand backgrounds, parameters of structures and processes of manufacturing, and some solutions to these problems are proposed. The development and research of composite cryotank in China are also prospected.