To provide a tapping screw which has good leading property to a prepared hole even if thrust force in screw work is reduced and prevent tumble of a screw at an initial stage of screwing.

A tapping screw is constituted of a head part 2 and a leg part 3 integrally with the head part 2, and a screw 10 of the leg part 3 has a normal screw part 11 of the same screw shape from a tip to a head part side. A guide screw part 12 having a diameter smaller than that of the normal screw part 11 is formed at the tip of the leg part 3, and a female screw forming part 13 having a diameter larger than that of the normal screw part 11 is formed between the guide screw part 13 and the normal screw part 11. The female screw forming part 13 is connected with the guide screw part 12 by a continuous screw so that the screw gets gradually higher. In the start of the screwing, the screw is bit into the prepared hole of the work without scraping the work, the screw can be screwed with relatively small thrust force, and a problem that turnings are scattered on an electronic part fixed to the work and damages the electric part, is solved.