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 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 (BA, BB) for the left and right coaxial front wheels (WA, WB) and between the brake fluid pressures of the wheel brakes (BC, BD) for the left and right coaxial rear wheels (WC, WD), 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 estimated vehicle body deceleration calculating means for calculating an estimated vehicle body deceleration of a vehicle, and the allowable differential pressure setting means sets the allowable differential pressure for the pair of the front wheels matching a road surface friction coefficient on the basis of the estimated vehicle body deceleration calculated by the estimated vehicle body deceleration calculating means, and the allowable differential pressure for the pair of the rear wheels matching the road surface friction coefficient on the basis of the estimated vehicle body deceleration calculated by the estimated vehicle body deceleration calculating means, characterized in that the allowable differential pressure setting means sets the allowable differential pressures matching the road surface friction coefficient on the basis of the estimated vehicle body deceleration after a control cycle of decreasing, maintaining, and increasing the brake fluid pressures is repeated at least two times in an anti-lock brake control for preventing the wheels from being locked. 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 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 (BA, BB) for the left and right coaxial front wheels (WA, WB) and between the brake fluid pressures of the wheel brakes (BC, BD) for the left and right coaxial rear wheels (WC, WD), 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 estimated vehicle body deceleration calculating means for calculating an estimated vehicle body deceleration of a vehicle, and the allowable differential pressure setting means sets the allowable differential pressure for the pair of the front wheels matching a road surface friction coefficient on the basis of the estimated vehicle body deceleration calculated by the estimated vehicle body deceleration calculating means, and the allowable differential pressure for the pair of the rear wheels matching the road surface friction coefficient on the basis of the estimated vehicle body deceleration calculated by the estimated vehicle body deceleration calculating means, characterized in that the allowable differential pressure setting means sets the allowable differential pressures matching the road surface friction coefficient on the basis of the estimated vehicle body deceleration after a control cycle of decreasing, maintaining, and increasing the brake fluid pressures is repeated at least two times in an anti-lock brake control for preventing the wheels from being locked.