Objective The present biomechanical model built for extravehicular activities (EVA) of astronaut is lack of human anatomy features, and still there isn’t a reasonable verification method. This study is aimed at solving the problems above and providing references for the further application of EVA simulation. Methods Based on a typical extravehicular activity, an inverse kinematical and dynamical upper limb model with muscle forces was built to conduct simulation calculation. Both the kinematical and dynamical results were verified through OpenGL animation sequence driven by kinematical calculation results and verification experiment with a real model, respectively. Results The animation built for kinematical verification proved that the calculation results were correct. The relative error of two muscle forces between dynamic verification and simulation was 14.54% and 0.91%, respectively. Conclusions A reasonable upper limb model of astronaut is established in this study. The simulation results are credible and the verification Results showed that this feasible method could supports the further research on EVA simulation and verification.