An anti-skid brake control system for a motor vehicle comprises: a wheel speed sensor which is provided for each wheel of the vehicle and generates a pulse signal having a pulse cycle which corresponds to a revolutional speed of each wheel; a pulse cycle measuring circuit for detecting the cycle of the pulses of the pulse signal from each wheel speed sensor; and, a discriminator for discriminating an actual acceleration or deceleration state. The actual acceleration or deceleration state is discriminated in accordance with whether or not the period of the acceleration or deceleration state is longer than a predetermined time. The acceleration or deceleration state is calculated from the wheel speed data detected by the pulse cycle measuring circuit, and the system is controlled on the basis of the result of the discrimination by the discriminator.