Abstract: Based on the application environment for ²³⁸PuO₂ radioisotope heat unit（RHU） and radioisotope thermoelectric generator（RTG） in china, The technical index system of safety for evaluating the safety for RHU/RTG is studied drawing on the safety verification of RHU/RTG in foreign countries. The framework of technical index system for the safety standards are propounded that includes the normal and unexpected emergency conditions of full life circle for the RHU and RTG, such as design and manufacture, stockpile and transportation on the ground, preparing for launch, launch, in-orbit operation waste disposal and so on. The technical index system includes 29 items that can be used as the reference in developing and assessing of safetyin-use about the Pu-238 radioisotope heat unit or radioisotope thermoelectric generator, solving the problem of lacking the safety certification system and technical index of safety verification for the use of space RHU/RTG in China.