PURPOSE: To form a screw hole on a panel without using a parts for forming the screw hole.

CONSTITUTION: A drawing part 2 having a specified opening diameter and a specified depth is worked at a specified position on a panel 1 in the 1st process, and a penetrating hole 3 of a specified diameter is worked at the bottom surface in the 2nd process. Then, by compressing the depth portion of the drawing part 2 in the 3rd process, the specified part of the panel 1 has an opening part on the center axis, and the circumferential panel thickness is increased by two or three times. When the panel thickness is thin and the tapping is impossible, the attachment of weld nut or a retainer is necessary in order to add the function as the screw hole, but because the opening part of the increased thickness is formed at the position of the screw hole, the tapping or the use of a self-tapping thread is possible without needing parts to form the screw hole.