Patent attributes
An electric booster including an input member that is advanceably/retractably moved according to a brake pedal operation. An electric motor of an electric actuator advanceably/retractably moves a power piston. A master pressure control unit sets a target movement amount of the power piston according to an amount of a movement of the input member that is caused by the brake pedal, and controls the electric motor to move the power piston so as to achieve the target movement amount, thereby causing a brake hydraulic pressure to be generated in a master cylinder. The master pressure control unit includes a reaction force generation portion, which changes a characteristic of a hydraulic reaction force applied to the brake pedal. The reaction force generation portion corrects the target movement amount of the power piston according to a temporal change in the movement amount of the input member.