To provide an antitheft screw which hardly gives rise to an axial deflection and eases fastening in addition to provision of the ability to prevent a screw from being cut while axially depressing the screw, and further provide fastening hardware for the antitheft screw and an antitheft screw set using them.

An antitheft screw includes a shaft 1 formed with a threaded portion 11 on its periphery and a head 2 formed integrally with one end of the shaft 1. The head 2 is further formed into an outer shape hard to get hold of with general tools such as a spanner, a wrench, a driver or the like. In the antitheft screw, the head 2 is formed with gripping portions 3 formed into a shape hard to get hold of with the general tools, and the gripping portion 3 are formed with a depressing face 4 capable of being depressed in the axial direction P of the shaft 1.