In this paper, five common modeling methods of human lower limb dynamics are compared and analyzed, and based on using Lagrangian method to acquire a dynamic model of human body stand phase. Human lower limb movement were analyzed by Matlab simulation software and proved the rationality of the model, also for the kinds of body dynamic modeling in the field of lower limb rehabilitation robot are summarized and prospect. The study provided reference and theory basis for design of lower limb rehabilitation robot.