A stapler includes a base, a first support portion disposed on the base, a support plate formed in the vicinity of the first support portion on each side of the base, a second support portion formed on the support portion so as to project therefrom, a staple storing magazine and an inner handle, both provided swingably on the first support portion, a driver plate disposed on the inner handle so as to strike out a staple, and an outer handle provided swingably on the second support portion. The outer handle includes a first handle member having a first half hole portion engageable with an upper portion of the two second support portion, and a second handle member having a second half hole portion engageable with a lower portion of the second support portion. The first handle member and the second handle member are connected integrally.