To provide an electric stapler that is configured to bias a clamp portion for clamping stapling paper sheets so as to adjust paper sheet thickness and capable of reducing a leaning of the clamp portion by restricting the biasing from being always performed.

The electric stapler includes: a clamp portion 13 for clamping stapling paper sheets in cooperation with a clincher mechanism 40 by moving relatively closer to and away from a clincher mechanism 40; and a biasing mechanism 14 for biasing the clamp portion 13 toward the stapling paper sheets. The biasing mechanism 14 releases the biasing on the clamp portion 13 at least when the clamp portion 13 is at a home position farthest from the clincher mechanism 40.