To provide an antitheft locking implement which maintains the strength of a claw member for being engaged with a lock hole of equipment, prevents a gap from being made in a lock hole, and achieves a claw member opening/closing operation in a simple structure.

This antitheft locking implement includes: a locking implement body in which the pair of claw members for being engaged with the lock hole of the equipment and an opening and closing mechanism for the pair of claw members is mounted and which is internally fitted with a cylinder for operating the opening and closing mechanism; a tether cable member mounting implement which is mounted on the locking implement body and provided with a protruding portion for mounting a tether cable member; a splittable cover member which is fitted into the locking implement body and which fixes the claw members and the opening and closing mechanism therefor in a sandwiching manner and holds them; and a fixing ring for integrally fixing the cover member. The claw member employs a means for being formed as a rectangular cross-section rod-like body which is formed in such a dogleg shape that a central portion is bent.