A punched piece is formed by punching a metal plate by a punching portion including by a die and a punch. Before the punching, a preceding process portion provided in a stage previous to the punching portion forms a projection at an inner peripheral portion of a punch area of the metal plate that faces the die. Forming the projection cancels formation of shear droop at an edge of the punched piece in forming of the punched piece by punching of the metal plate.