PURPOSE: To provide high responsive anti-skid control with the use of an anti- skid control device of simple construction, by electro-magnetically operating only one selector valve part so that hydraulic pressure in a wheel cylinder is discharged to a reservoir in association with a signal from a control circuit which detects wheel lock.

CONSTITUTION: A valve mechanism in which a control piston 8 disposed in cylinders 5, 7 and biased leftward by a spring 9 is slidably fitted in a valve body that is formed by uniting bodies 1 through 3 with bolts fastening them together, for communicating and shutting off brake fluid flow from a master cylinder M/C to wheel cylinders W/C. The control piston 8 defines two chambers (a, b), the outlet chamber (b) being communicated with a reservoir fluid chamber (d) through a fluid chamber (c) by means of a solenoid valve including a spherical valve 17 which is actuated by a solonoid 12 through a moving iron core 13 and a rod 14. Furtyer, fluid in the fluid chamber (d) is sucked up to the fluid chamber (b) by means of a pump mechanism including a plunger 24 driven by rotation of a cam 25.