In a motorcycle provided with an antilock brake system, a front fork supporting a front wheel of a motorcycle is supported to be rotatable by a head pipe which is located at the front end portion of a body frame of a motorcycle, a handle-bar is secured to an upper end portion of the head pipe, master cylinders attached to the handle-bar are connected to hydraulic wheel brakes, respectively, via brake pipes. An antilock brake system includes an ABS-unit for antilock control disposed in an intermediate portion of the brake pipes. The ABS-unit is disposed immediately behind the head pipe and between a pair of body frame components disposed on both lateral sides of the motorcycle body and extending, from the head pipe, obliquely downward and backward, while extending outward in directions opposite to each other in the width direction of the motorcycle body.