Abstract: From the current state of the civil satellite reliability assurance, and a comparison with those of NASA and ESA, the reliability assurance model based on satellite product assurance is analyzed, with special consideration of the development demand of GJB 450A, and the role of reliability assurance model under product assurance is discussed, including the internal relation with increased satellite operating stability and reliability. It is shown that the reliability assurance under product assurance is the necessary trend of satellite reliability, and the emphases of satellite reliability assurance are on reliability design, reliability analysis, reliability test, management based on life cycle analysis of satellites, and the basic studies in the satellite reliability development.