Abstract: The attitude and position accuracy of the space membrane deployable mechanism will affect the working pattern of the membrane cable network. In this paper, a theoretical model of motion accuracy reliability of the annular truss space membrane deployable mechanism was constructed, and a parametric simulation model considering the rod length error of the deployable mechanism was established based on ADAMS. The motion accuracy reliability simulation analysis of the deployable mechanism was carried out by Monte Carlo method to solve the motion accuracy reliability. The results indicate that it is correct to take both the spatial circle center coordinate position error and the radius error, fitted by the supporting points of the foldable rod of the fully deployed annular truss space membrane deployable mechanism, as the quantitative index for evaluating the motion accuracy reliability. The research may provide a reference for the reliability-based design of space membrane deployable mechanism.