Abstract: A motor-driven friction braking device for a rail vehicle is mainly composed of a torque motor, a speed reduction mechanism, an electromagnetic brake (1), a screw nut transmission mechanism and a brake friction pair (9). The torque motor, a screw (7), the speed reduction mechanism and the electromagnetic brake (1) are coaxially mounted; the torque motor is fixedly connected to the speed reduction mechanism, and the speed reduction mechanism is fixedly connected to the screw (7); the screw (7) is in non-self-locking threaded connection with a nut (8), and one end of the nut (8) is connected to the brake friction pair (9); and the electromagnetic brake (1) is mounted on the screw (7).