To start or stop the train safely within the limited traveling distance, it is necessary to guarantee the proper traction or braking force. Presently, most trains are run by the electrical power and have adopted a combined electrical and mechanical(friction) braking system. In order to design a good traction or a brake system, it is essential for designers to predict the traction or brake performance. In this paper, the traction/coasting/braking performances analysis program has been developed and verified by comparing the simulation results with on-line test results of the Korean high speed train(HSR-350); Both results match very well. Consequently, the designers can predict the traction/coasting/braking performances of trains by using the proposed program under various operating conditions.