A rivet setter which can efficiently and smoothly perform the rivet setting operation even when setting rivets each having a shank of its length smaller than a diameter of its head. The rivet setter can be configured to set a rivet sequentially fed one by one from a rivet supplying means by inserting the rivet into apertures formed at predetermined positions on workpieces. The rivet setter can comprise delivery paths for delivering the rivet one by one by forcing the rivet to be slid down to a settable position. The rivet setter can include notches formed on the bottom surfaces of the delivery paths along the rivet delivery direction and extending to the settable position for supporting the head of the rivet in the course of delivery of the rivet on the delivery paths and for hanging the shank of the rivet downward.