A bending device includes a fixed mount having a chuck mechanism gripping a workpiece is attached thereon, and an articulated robot which moves a bending mechanism attached thereto. The articulated robot is provided with a plurality of swinging joints which perform swinging operation and a plurality of pivoting joints which perform pivoting operation. The workpiece is clamped between a bending die and a clamping die. The bending mechanism is moved by the articulated robot so that the workpiece is gripped by the chuck mechanism. At the same time, the chuck mechanism is moved by the articulated robot to bend the workpiece at a plurality of positions. After the bending, while the workpiece is clamped between the bending die and the claimping die, the gripping by the chuck mechanism is released. The bending mechanism is moved by the articulated robot so that the workpiece is discharged.