To improve the replacement workability of a refill of an electric stapler.

A corner of a guide flap 3 bent in an L shape is pivoted in a driver unit 1 of the electric stapler so that a front part of the guide flap projects into a pass for staple cartridge insertion. A holding lever 7 is mounted to a rear part which is bent with respect to the front part, and a spring 8 is interposed between the rear part and the holding lever. When a staple cartridge 11 is loaded to the driver unit, the guide flap is rotated by being pressed by the staple cartridge and the holding lever of the guide flap holds the upper surface of a staple sheet in the staple cartridge. Even if equipment is arranged in a way which prevents visually recognizing an inserting hole of the staple cartridge, it is easy to replace the cartridge. The holding lever is arranged in the driver unit rather than the cartridge, thereby it is possible to achieve a small and lightweight staple cartridge.