A fastener includes a belt (10), a buckle (12) connected to the belt and having an inlet end (14a) and an outlet end (14b), and a pair of protection portions (18) formed in the outlet end of the buckle. The belt and the buckle are arranged and constructed to be locked to each other when the belt is tightened after the belt is inserted into the buckle and drawn therefrom. The protection portions (18) are arranged and constructed to respectively face longitudinal peripheries edges (10d) of the belt that is inserted into the buckle and drawn therefrom. Each of the protection portions has a projection amount (H) not less than a length (L) of a remaining portion (S) of the belt, which portion (S) can be produced by cutting off an excess portion of the belt drawn from the buckle.