A fluid-pressure brake device (100) for a vehicle, provided with: a brake operating element (10), a master cylinder (20), wheel cylinders (FL, FR, RL, RR), an actuator (30) for fluid-pressure control, a fluid-pressure control circuit (40), an electric control device (50) and the like. Furthermore, in the fluid-pressure brake device (100) for a vehicle are disposed: master system fluid-pressure circuits (31, 32) connecting pressure chambers (C3, C4) of the master cylinder (20) and pressure chambers of the wheel cylinders (FL, FR, RL, RR), as well as normally closed electromagnetic open-closed valves (V8, V9) located in passages (P1, P2) connecting the master system fluid-pressure circuits (31, 32) and a driving fluid chamber (C2) of the master cylinder (20). The electromagnetic open-closed valves (V8, V9) are set so as to open when actuation amount of the brake operating element (10) is equal or greater than a set value. As a result, it is possible to reduce the size and stroke of the master piston in the master cylinder.