PURPOSE: To provide a brake device for a wheel which can realize the approach of the brake power distribution for the front and rear wheels always to the ideal distribution, independently of the variation of the load weight, by suppressing the increase of the dimension of the device and cost-up to the min.

CONSTITUTION: As for a brake device which is constituted so that a control module 8 compares the relation between the brake operation force applied from a brake pedal 5 and a brake force and outputs a control instruction for the hydraulic pressure in a control chamber 3 into a control valve 7 and the operation of the brake is controlled, a master cylinder 6 is allowed to communicate to a front wheel brake 12, and a rear wheel brake 13 is allowed to communicate to the control chamber 3 of a hydraulic booster 4. The hydraulic pressure in the control chamber 3 increases at the rate larger than the output pressure of the master cylinder when the load increases, and in case of the common vehicle in which the weight distribution on the rear wheel side is increased by the increase of the load, the distribution of the brake power to the rear wheel increases in the increase of load, and the approach to the ideal distribution is realized.