To provide a bolt which can appropriately control its axial force when fastened.

The bolt comprises a bolt body 4 having a receiving hole 3 drilled therein so as to pass through in the axial direction, a rod 5 which is inserted into the receiving hole 3 over its whole length and has a head portion 9 brought into contact with the bottom surface of a recessed portion 7 formed on one end portion of the bolt body 4, and a nut 6 which is screwed on a threaded portion 10 of the rod 5 and is brought into contact with a recessed portion 8 formed on the other end portion of the bolt body 4 so as to keep the tension of the rod 5, wherein the shape of the rod 5 and the material to be used for the rod 5 are selected such that the rod 5 can be broken when a specified axial force has been applied to the bolt body 4. In other words, when the axial force of the bolt body 4 has increased up to the specified value by the fastening operation, the rod 5 breaks, and it can be surely judged that the axial force of the bolt body 4 has reached the specified value.