There is provided a brake system for vehicles, the brake system including: a slave cylinder S/C to generate a hydraulic pressure by an electric motor according to a braking operation by a driver; and a controller to decrease an operation amount of the slave cylinder S/C when an operation amount of the electric motor is maintained, then increase an operation amount of the slave cylinder S/C when a change occurs in an operation amount of the electric motor subsequently. The controller determines whether or not the phase currents Iu, Iv, Iw of the electric motor are in two-phase continuously energized state and the state remains for a certain time or longer. When the determination conditions are satisfied, the controller performs commutation control to generate commutation in the electric motor by reducing a target hydraulic pressure of the slave cylinder S/C.