An electronic brake system is disclosed. An electronic brake system according to an embodiment of the present invention may be provided to comprise: a reservoir in which a pressurization medium is stored; an integrated master cylinder comprising a simulation chamber, a simulation piston provided in the above-mentioned simulation chamber such that same can be displaced by a brake pedal, a master chamber, a master piston provided in the master chamber such that same can be displaced by a displacement of the simulation piston or by a liquid pressure of the simulation chamber, an elastic member provided between the simulation piston and the master piston, a piston spring for elastically supporting the above-mentioned master piston, a simulation channel connecting the above-mentioned simulation chamber and the above-mentioned reservoir, and a simulation valve provided in the above-mentioned simulation channel so as to control the flow of the pressurization medium; a liquid pressure providing unit for actuating a hydraulic piston according to an electric signal which is output in response to a displacement of the brake pedal, thereby producing a liquid pressure; a hydraulic control unit having a first hydraulic circuit for controlling a liquid pressure delivered to two wheel cylinders, and a second hydraulic circuit for controlling a liquid pressure delivered to two other wheel cylinders; an electronic control unit for controlling valves on the basis of liquid pressure information and brake pedal displacement information; a backup channel connecting the simulation chamber and the above-mentioned first hydraulic circuit; an auxiliary backup channel connecting the above-mentioned master chamber and the backup channel; and an inspection valve provided in the above-mentioned auxiliary backup channel so as to control the flow of the pressurization medium.