To provide an anti-lock braking device attached between a master cylinder and a cylinder pipe feeding oil pressure for a vehicular brake and preventing a locking phenomenon of the brake occurring during braking by storing a part of the oil pressure transmitted to wheels and continuously and dividedly feeding it during vehicular braking.

A sealing member 30, a piston shaft 40 and a supporting boss 20 vertically moved by expansion and restoration by feeding of the brake oil pressure are integrally supported. Durability of the supporting boss 20 and the piston shaft 40 is improved by using a metal material, rubber made buffer rings 63 and 73, a small disc spring 70 and a large disc spring 60 are provided in an interior of a cylindrical guide bush 6 supporting the sealing member 30 of a rubber material, and pressure can be transmitted while flexibly corresponding in three stages to change of braking pressure. It is characterized by that it can be attached to both small and large vehicles by providing a randomly adjustable pressure regulating valve 90 in a lowermost part.