To provide a nail for a hard material as driving object, which can be easily driven to steel product, concrete or the like, and is hardly dropped out with an extremely large retaining strength after it is driven.

This nail comprises a nail head part 12 with wide diameter formed at one end side of a round bar-like nail body part 11, and a shell-shaped nail tip part 14 continued to the other end side of the nail body part 11 through a narrowed part 13. The base end 14a side of the nail tip part 14 is formed to be smaller in diameter than the nail body part 11, and this difference in diameter is reduced in the constricted part 13.