A vehicle brake fluid pressure control apparatus including: a fluid pressure adjusting unit capable of performing adjustment of individually increasing and decreasing brake fluid pressures acting respectively on wheel brakes for front wheels and wheel brakes for rear wheels so as to prevent the front wheels and the rear wheels from being locked during braking; and allowable differential pressure setting means for setting allowable differential pressures allowable between the brake fluid pressures of the wheel brakes for the left and right coaxial front wheels and between the brake fluid pressures of the wheel brakes for the left and right coaxial rear wheels, the operation of the fluid pressure adjusting unit being controlled in such a way that each of the differential pressures between the brake fluid pressures of the wheel brakes for the left and right coaxial front wheels and between the brake fluid pressures of the wheel brakes for the left and right coaxial rear wheels is equal to or lower than a corresponding one of the allowable differential pressures set by the allowable differential pressure setting means, wherein the vehicle brake fluid pressure control apparatus comprises fluid pressure acquiring means for acquiring a lock fluid pressure of a wheel brake of a wheel coaxial with and other than a wheel being a control target, the lock fluid pressure being a fluid pressure at which pressure decrease by an anti-lock brake control is started, and the allowable differential pressure setting means sets the allowable differential pressures matching a road surface friction coefficient on the basis of at least the lock fluid pressure obtained by the fluid pressure acquiring means, characterized in that the fluid pressure acquiring means calculates the lock fluid pressure on the basis of an output fluid pressure of a master cylinder common to the wheel brakes and drive electric currents of electromagnetic valves forming part of the fluid pressure adjusting unit. a fluid pressure adjusting unit capable of performing adjustment of individually increasing and decreasing brake fluid pressures acting respectively on wheel brakes for front wheels and wheel brakes for rear wheels so as to prevent the front wheels and the rear wheels from being locked during braking; and allowable differential pressure setting means for setting allowable differential pressures allowable between the brake fluid pressures of the wheel brakes for the left and right coaxial front wheels and between the brake fluid pressures of the wheel brakes for the left and right coaxial rear wheels, the operation of the fluid pressure adjusting unit being controlled in such a way that each of the differential pressures between the brake fluid pressures of the wheel brakes for the left and right coaxial front wheels and between the brake fluid pressures of the wheel brakes for the left and right coaxial rear wheels is equal to or lower than a corresponding one of the allowable differential pressures set by the allowable differential pressure setting means, wherein the vehicle brake fluid pressure control apparatus comprises fluid pressure acquiring means for acquiring a lock fluid pressure of a wheel brake of a wheel coaxial with and other than a wheel being a control target, the lock fluid pressure being a fluid pressure at which pressure decrease by an anti-lock brake control is started, and the allowable differential pressure setting means sets the allowable differential pressures matching a road surface friction coefficient on the basis of at least the lock fluid pressure obtained by the fluid pressure acquiring means, characterized in that the fluid pressure acquiring means calculates the lock fluid pressure on the basis of an output fluid pressure of a master cylinder common to the wheel brakes and drive electric currents of electromagnetic valves forming part of the fluid pressure adjusting unit.