Abstract: To meet the requirement of long-term operation of our country’s deep space exploration missions, a passive and highly reliable heat pipe reactor is chosen as the power source. In order to achieve a light mass, UMo with high uranium density, enough high temperature mechanical properties and irradiation stability is selected as the reactor fuel. Na heat pipe with Haynes cladding is chosen for heat transfer. The heat pipes are placed inside the fuel. Brazing or Liquid Interface Diffusion can be used as the integrated method between the heat pipes and the fuel. Static thermoelectric technology, which possesses a long life and rich successful experience, is chosen as the power conversion system. And Half-Heusler with suitable operation temperature and high efficiency is selected as the conversion material. In order to achieve an ultra-long life, a burnable poison control scheme and a variety of creative and passive control schemes to increase the negative temperature coefficient of the core are proposed. The final power scheme is expected to meet the needs of our country’s deep space exploration missions.