To enable a trouble diagnosis of braking-input-side pressure sensors even in a state where a braking input side and a braking output side are interrupted from each other. In a brake device of a vehicle in which a braking input side which generates a liquid pressure by manipulating a brake manipulation portion and a braking output side which supplies the liquid pressure to a brake caliper are made to be communicated with each other or being interrupted from each other by way of a first electromagnetic open/close valve, and the brake device includes a hydraulic modulator which adjusts the liquid pressure of the braking output side by operating an electrically-operated motor, the brake device includes a first pressure sensor and a second pressure sensor for detecting the liquid pressure of the braking input side, and a trouble diagnosis of the pressure sensors is performed in response to detection values of the pressure sensors.