In order to operate trains efficiently at high speeds regardless of their length, control systems that can provide stable braking forces must be developed. In the designing brake control systems, it is essential to consider the robustness because there are model uncertainties that result from nonlinear characteristics for adhesion and the brake material friction coefficient. This paper presents an innovative new wheel slip prevention control system that utilizes sliding mode control. Simulations for the proposed wheel slip prevention control system are performed and compared with some conventional control laws. The results of simulation prove the effectiveness of the proposed control system as compared with conventional types, and show the high brake performance under non-linearity of brake dynamics.