Provided is a vehicle brake system including a master cylinder which generates a master hydraulic pressure through an operation of a brake pedal by an operator, and a cylinder body which houses a first and second slave pistons driven by an electric motor operated in accordance with an operation amount of the brake pedal, and is formed with a first hydraulic chamber and a second hydraulic chamber for generating a slave hydraulic pressure through operations of the first and second slave pistons. Further, the cylinder body includes a first bleeder and a second bleeder which are configured to be switchable between open states in which a first hydraulic chamber and a second hydraulic chamber are in communication with an external of the cylinder body and closed states in which the first hydraulic chamber and the second hydraulic chamber are not in communication with the external of the cylinder body.