Detachable anti-loosing and anti-theft bolt structure

The invention relates to a fastening piece, in particularly a detachable anti-loosing and anti-theft bolt structure. The detachable anti-loosing and anti-theft bolt structure mainly comprises a bolt and a nut, and is characterized in that a threaded section of the bolt comprises an upper section and a lower section which are fabricated integrally; threads of the upper section and the lower section are same; the diameter of the upper section is smaller than that of the lower section to ensure that the threads of the upper section does not contact the threads of the nut; the threads of the upper section and the threads of the lower section are staggered for a half screw pitch to ensure that gear peaks and gear valleys of the threads of the upper section are opposite to gear peaks and gear valleys of the threads of the nut; a snap spring which is made of a shape memory alloy material is accommodated in a space which is formed by at least one circumferential gear valley; and the threads of the lower section of the bolt are matched with the threads of the nut. The detachable anti-loosing and anti-theft bolt structure can be screwed down by using a standard tool to realize a reliable self-locking function, and the nut cannot become loosed automatically, so that the detachable anti-loosing and anti-theft bolt structure has high anti-loosing and anti-theft function. When the detachable anti-loosing and anti-theft bolt structure is required to be disassembled, the nut is heated to ensure that the snap spring is separated from the nut, and then the bolt can be unscrewed by using a wrench, so that the conventional destructive disassembly is avoided, and waste is reduced.