Power train modeling brings a great deal of inconvenience to the research of vehicle for its complication and long period. Modeling and simulating with professional software can increase efficiency obviously. By introducing the functions and characteristics of CRUISE, a simulation model of manual transmission is built. This software is not only convenient, simple and universal, but also direct-viewing and easy to debugging. With this software, a large amount of time is saved and simulation results and modify parameters are analyzed expediently; therefore, system design can be achieved fleetly.