Abstract: The joint clearance is one of the important factors affecting the precision and stability of mechanical systems, especially under various extreme conditions of space microgravity environment. In this paper, the origin, development, and application of clearance modeling methods such as the two-state model, the continuous contact model, and the three-state model are reviewed. For the spacecraft mechanism with clearance, the influences of the clearance on the dynamic characteristics and related ground simulation experiments, as well as the research progress of joint wear and lubrication characteristics have been summarized and analyzed. And some future research directions are proposed in the field of spacecraft mechanism with clearance under space environment.