To provide a method of forming a metal sheet, by which a stage for obtaining a formed article having a U-shaped cross section is shortened.

First, a hole 2 is formed with a punching punch or the like on the circular part of the prepared metal sheet 1 having a circular part. Next, the inner peripheral part 3 and the outer peripheral part 4 of the metal sheet 1 on which the hole 2 is formed are bent preliminarily at the same time in the same direction. Then, the outer peripheral part 4 is formed so as to be extended longer than the inner peripheral part 3. Next, by forming the final bending of the inner peripheral part 3 and the outer peripheral part 4 which are bent preliminarily at the same time, the formed article 5 having the U-shaped cross section is obtained. In this final bending stage, the inner peripheral part 3 and the outer peripheral part 4 are parallel to each other and the outer peripheral part 4 is formed so as to be extended longer than the inner peripheral part 3.

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