PURPOSE: To simply and quickly form various frames by automatically forming a metal frame for reinforced concrete.

CONSTITUTION: In a metal frame, an auxiliary rod 29 is welded so that a plurality of stirrups 30 are connected one another at specific intervals and the rod 29 that is longer than is wide is fixed to the inner side of the stirrups 30. A forming device is equipped with a fixing-type frame work 1 with a welding means and a welding table 41, a guide 2 that is longer than is wide for guiding the formed frame, and a movable type upper mechanism 3 with gripping means 51 and 52 for gripping one end part of the auxiliary rod for moving. In a forming method, the stirrups 30 are supplied onto the welding table 41. Then, the auxiliary rod 29 is welded to the stirrups 30. Then, while the gripping means 51 and 52 grip one end of the auxiliary rod 29, the upper mechanism is advanced for sending the frame.