A package for receiving electronic parts is formed with decreased stress and stress concentration to obtain a desired warp and flatness. In particular, according to a cutting protruding part process, a package is accommodated to have a recessed part formed on one face of a metal plate by pressing the face of the metal plate so that a corresponding protruding part is formed bulging from an opposing face of the metal plate. The protruding part is cut by a cutting tool and a bottom which has a cavity shape and is thinner in size than the metal plate is formed at the recessed part. The protruding part is again formed bulging from the metal plate and cut by the cutting tool. The cutting direction is differed in alternately facing directions so that the stress from cutting is almost cancelled.