While driving one motor, an electronic wedge brake (EWB) system according to an embodiment of the present invention implements a main braking function by self-energizing caused by a wedge operation. Since only one motor is used, it is possible to reduce the number of parts and to simplify the structure. Further, the electronic wedge brake system implements various functions, such as a function for maintaining a set clearance of a pad, a wheel lock prevention function, and an EPB function by using a solenoid interlocked with a NSL (Non-Self Locking) type screw that is moved in an axial direction and supports an axial reaction force transmitted from a pad. Furthermore, a NSL (Non-Self Locking) type push rod shaft, which supports the axial reaction force, is constrained using power of the motor during park braking, and accordingly, even when the solenoid is turned off, it is possible to stably and reliably park a vehicle.