Abstract: The structure of the payload adapter was becoming more and more complex to meet the needs of the new spacecraft. In order to offset the large deviation of the center of mass of a reentry spacecraft and realize the self-leveling of separation design, a payload adapter with irregular shape was designed according to the structural characteristics of a reentry spacecraft. Based on the analysis of the characteristics of riveting technology and additive manufacturing technology, two different process schemes of riveting and additive manufacturing were compared and analyzed. According to the actual manufacturing precision measurement needs of the payload adapter with irregular shape, laser tracking measurement technology was selected as the precision measurement method. Through the application case analysis of axis measurement after the installation of a certain type of upper-stage engine nozzle, it can be seen that the measurement and data processing method based on laser tracker and least square method could be applied to the payload adapter with irregular shape. And the obtained accuracy data could be used as the basis for the separation of spring selection in the subsequent separation design.