To provide an electric stapler having a simply structured, reliably operated, and inexpensive clinching mechanism capable of avoiding a load applied on a drive part by folding leg parts of a staple at an appropriate timing while maintaining a clincher rotation angle to an adequate value, and lightening an applied load depending on the thickness of a paper bundle.

The clinching mechanism of the electric stapler in which the leg parts of the staple penetrating the paper bundle are folded flatly in their inner directions comprises: a gear interlocked with driving of the staple; a cam integrally revolving with the gear; a push-down part which is an approximately isosceles triangle with the top part oscillating vertically by being pressed by a rim of the cam, one end engaged with a fixed shaft, and the other end engaged with a push-up part through an engaging shaft; the push-up part pivotally supported by a center shaft with the tip end engaged with a clinching pedestal and the rear end engaged with the push-down part; an elastic body; and the clinching pedestal having a clincher that folds the staple flatly.