Theft-proof screw bolt

The utility model provides a theftproof bolt which comprises a bolt with a screw cap, a nut, and an axial notch arranged on the bolt. The utility model is characterized in that wedge-shaped pins are arranged in the axial notch. Through the wedge-shaped pins with different big heads and small heads, when being embedded in the axial notch between the bolt and the nut, the theftpoof bolt damages an internal screw thread of the nut to ensure that the nut is hard to be disassembled from the bolt, namely, even when overexerting, the nut is also hard to be disassembled, thereby playing the theftproof role in deed, in addition, the section shape of the wedge-shaped pin can be arranged to be suitable for the shape of the axial notch on the bolt, and can also increase the breakage to the internal screw thread of the nut, so as to ensure the theftproof performance of the bolt and the nut, and put an end to the happening of stealing affairs radically.