A shielded metal arc welding machine having a characteristic with a constant current output characteristic and a drooping output characteristic properly combined is provided. A shielded metal arc welding machine having a constant current output characteristic, characterized by having a desired drooping output characteristic, which has an optional drooping degree with a point at which a characteristic line of said constant current output characteristic intersects a welding load characteristic line L as a base point, and replaces said constant current output characteristic.