The modeling and simulation for a robot system with system simulation tools can make it possible to complete its performance evaluation，scheme reasoning and so on with economy，convenience and high-efficiency .In this way，the high reliability of system design. Correctness and optimal performance of product can be guaranteed .It also can shorten designing period and reduce development cost. In addition，a novel method for modeling and simulation of robot system based on the mathematical model has been proposed .The final simulation results meet the request of system performance，and testify the applicability and effectiveness of the design method .This novel method offers a new thought way for designing actual robots.