Abstract: In this paper, the working principle and research status of metal hydride heat pump are introduced, its application possibility to the life support system of manned space flight is analyzed. A comparison is made between different heat sinks, including water sublimator, phase change heat storage and metal hydride heat pump, from the aspects of size, weight, power, material waste and recovery time. The analysis shows that metal hydride heat pump system has wide application prospective in manned space flight. Some key techniques which must be considered firstly are stated.