BRAKE DEVICE AND METHOD OF CONTROLLING BRAKE DEVICE

[TASK] It is an object to provide a brake device and a method of controlling the brake device, capable of suppressing an inrush current during a startup period of an electric booster. [MEANS TO SOLVE] In a brake device having an input rod, a piston for pressurizing a fluid pressure in a master cylinder responsively to a displacement of the input rod, and an electric booster for pushing the piston against a spring bias of a return spring of the piston and for assisting a movement of the piston in a direction for pressurizing of the fluid pressure, an input-rod displacement detection device is provided for detecting the displacement of the input rod. Also provided is an electric-booster controller configured to start up the electric booster, while applying an assisting force to the piston to push the piston against a biasing force, which forces the piston in a direction for reducing of the fluid pressure in the master cylinder, upon detecting that the input rod has been displaced a predetermined displacement at the time when a driver's brake-pedal operation starts.