Disclosed are an electronic brake system and an operating method thereof. The electronic brake system according to the present embodiment comprises: a reservoir having a pressurization medium stored therein; an integrated master cylinder having a master piston, a master chamber of which the volume varies according to the displacement of the master piston, and a sealing member sealing the master chamber; a simulator valve that controls the flow of the pressurization medium between the reservoir and the master chamber; a hydraulic supply device that operates a hydraulic piston on the basis of an electrical signal output in response to a displacement of the brake pedal and generates hydraulic pressure; and a hydraulic control unit provided between the hydraulic supply device and a plurality of wheel cylinders, wherein whether a component element including the integrated master cylinder leaks may be determined on the basis of an inspection flow path connected to the master chamber and an inspection valve provided in the inspection flow path.