PURPOSE: To prevent a fail-safe operation during the anti-skid control by prohibiting the operation of a failure judgment means outputting a failure signal during the anti-skid operation when the speed difference of wheel speeds of individual wheel speed systems reaches a predetermined value or more.

CONSTITUTION: When the preset deceleration is attained by quick braking, the anti-skid control is performed. The AV signal of an AND gate 30 is made H, the a retriggerable timer 44 is activated, and the drive motor 52 of a liquid pressure recovery pump is activated. At the same time, AND gates 64aW64c are made an inhibit state, and the failure judgment outputs from comparators 62aW 62c are prohibited from being inputted to timers 66aW66c. Accordingly, even if the speed difference of individual wheels exceeds a predetermined value δ and either of the comparators 62aW62c generates a failure judgment output, the AND gates 64aW64c are in an inhibit state, thus preventing the fail-safe operation to release the anti-skid control due to the erroneous failure detection during the anti-skid control.