To prevent a rivet having a relatively long leg from swelling and bending during caulking thereof.

A rivet 1 is composed of a head part 2, a leg part 3 formed therein with a bore 11 extending in the front end part thereof on the center axis thereof, and a plurality of annular grooves 12 formed in the outer periphery of the front end of the leg part 3. Accordingly, the rivet can be prevented from swelling and bending during caulking thereof. Further, a workpiece can be firmly caulked when the rivet is caulked with the workpiece, without workipiece floating up. Further, since the rivet can be prevented from swelling and bending even though the rivet has not such a stepped shape that the barrel part of the leg part is thick but the front end thereof is thin, the manufacturing cost can be reduced. Moreover, the annular grooves are formed deeper and deeper toward the front end of the leg part, the flaring of the front end thereof can be smoothly and surely made.