A wearable electronic device includes an external housing including a first surface, a second surface toward a direction opposite to the first surface, and a first opening formed through the first surface; a display disposed in the opening; a plate covering the display, forming at least a portion of the first surface, and having a substantially circular shape; a first structure forming a portion of the external housing or extending from the external housing; a bezel surrounding an outer circumferential surface of the plate, mounted on the external housing to be rotatable, and including a surface toward a portion of a surface of the first structure; and a second structure disposed between the portion of the surface of the first structure and the surface of the bezel and attached to the first structure. The second structure has a friction coefficient smaller than a friction coefficient of the first structure.