An anti-skid control system for an automotive vehicle is provided with an actuator which is disposed in a hydraulic circuit between a pressure generator and a wheel brake cylinder. The actuator is arranged to control the hydraulic braking pressure applied to the wheel brake cylinder. In response to a wheel speed detected by a wheel speed detector, it is determined in an electronic control unit whether a condition for decreasing the braking pressure is effected. When this condition is effected, the decrease mode is provided in the control unit. When a predetermined period of time lapses after the decrease mode is initiated, the decrease mode is turned to a pressure control mode for applying the braking pressure to prevent the road wheel from being locked. When the condition is not effected during the predetermined period of time after the decrease mode is initiated, the decrease mode is turned to a direct supply mode for directly communicating the pressure generator with the wheel brake cylinder. Consequently, the lack of braking force caused by the delay of timing for decreasing the hydraulic braking pressure due to an erroneous detection of a locking condition of the road wheel on a rough road is effectively prevented.