A snap button includes a female snap body and a socket ring. The female snap body includes a bottom portion and a side wall rising from a peripheral edge of the bottom portion, the side wall provided with a holding portion for holding the socket ring. The socket ring includes a flange portion arranged radially outward and held by the holding portion and an engaging portion arranged radially inside the flange portion. The engaging portion protrudes downwardly toward the bottom portion side of the female snap body and below the flange portion, in the axial direction of the socket ring. An inner diameter of the socket ring may be gradually increased from an intermediate point in the axial direction of the engaging portion to one end and other end in the axial direction of the engaging portion. The engaging portion of the socket ring may be provided with a plurality of slits along the radial direction in the circumferential direction.