A method for manufacturing a linear cutter permits continuous manufacturing of linear cutters and achieving remarkable reduction in processing steps, processing time, and a process cost, and is immediately feasible to linear cutters having special lengths. The method includes the steps of: preparing a pair of roller dies for forming a die hole for processing a wire rod into a predetermined shape, the die hole having keen angle parts for forming a cutting edge; and causing the wire rod to pass through the die hole in a state that the roller dies revolve and thereby forming a sectional shape of the wire rod into a pre-set shape and, at the same time, forming a cutting edge at least at one edge of the wire rod.