To provide a method for cutting a dreg dividing line for film dregs outside a cut film.

According to shape data of a cut film, data regarding a cut framework line surrounding the external circumference of the cut film 30 is formed and memorized in a memory circuit 112. In accordance with such data, dreg dividing line data designed to divide film dregs 40 into multiple portions is formed and memorized in the memory circuit 112. Using these data, the cut film 30, the cut framework line 50, and the dreg dividing line 42 are shown on a display 1120. Further, after the dreg dividing line data memorized by the memory circuit 112 is modified as needed, a cutting plotter is moved according to these data, thereby cutting the dreg dividing line 42 for dividing the cut film 30, the cut framework line 50, and film dregs 40 into multiple groups on the film 20.