To cut a workpiece easily into small pieces by providing a cutter movably in an X-axis direction or a Y-axis direction, and providing a workpiece placing base, provided with a workpiece rotating device, movably in the Y-axis direction or the X-axis direction.

A turntable 45 is rotated by torque of a turntable driving motor 55 through a speed reducer 57 and stopped by operating a brake of the speed reducer 57 in a position where one blade W of a large screw faces a Y-axis direction. A workpiece placing base 33 is advanced on a placing base guide rail 39 by the actuation of a placing base driving motor 41 and stopped in the advanced position of the tip of the blade W. In this state, a vertical band saw machine 1 advances at low speed on a guide rail 25 and advances while cutting the workpiece with a band saw blade 7 traveling from an upper frame 19 of the vertical band saw machine 1 toward a lower frame 15.