Abstract: A mathematical model was proposed to describe the aircraft brake process. Firstly, analyzing the force of the aircraft and its wheels, a series of dynamic equations were established to solve the key variables in the entire braking process. And then, a Runge-Kutta method was used to obtain the solutions of differential dynamics equations. Finally, a hardware-in-the-loop simulation platform RTX was established to simulate and guarantee the real-time performance. Results show that, the simulation system can adapt for the experimental parameter changes to simulate the braking process under different actual conditions.