Abstract: An electric discharge contour machining method in which a plurality of rod-shaped portions having different outer diameters on one rod-shaped electrode are used to machine the contour shape of a workpiece. The workpiece is selectively machined in any of a plurality of contours by the single electrode having an optimum electrode diameter for each selected contour. Specifically, the method uses one rod-shaped electrode having a plurality of rod-shaped portions, each portion having a different outer diameter such that the workpiece contour having a small inner corner of first radius R is machined by the electrode portion having a small outer diameter and the workpiece contour having a large inner corner of second radius R is machined by the electrode portion having a large outer diameter.