The invention provides a brake system and a brake processing method for a rail transit vehicle. The brake system for the rail transit vehicle comprises a brake instruction generating device, a brake control device and a brake executing device, wherein the brake instruction generating device is connected with the brake control device; and the brake control device is connected with the brake executing device and a sensor respectively. By the brake system and the brake processing method, the optimal braking force value for a brake action can be acquired according to the real-time state of a train and the brake action is performed by using the optimal braking force value, so the braking distance of the rail transit vehicle can be effectively shortened; wheels are prevented from sliding; the safety of train operation can be improved; a wheel tread can be effectively protected; and the service life of the wheels is prolonged.