A snap button wherein when a male snap is removed from a female snap, a rotation between the snaps is limited, but is permitted normally. A male-side grooved surface is provided on a male snap radially outward from a projection of the snap with a plurality of grooves formed so that peaks and troughs of the grooves are arranged continuously in the circumferential direction. A female-side grooved surface similar to the male-side grooved surface is provided on a female snap radially outward from a projection-receiving space of the snap. The female-side grooved surface is inclined relative to the male-side grooved surface. When the male snap is removed from the female snap, each axis of the male snap and the female snap, which are yet in a coupled state, inclines relative to each other, causing the male-side grooved surface and the female-side grooved surface to partially engage with each other.