To provide a bending method using a robot for removing the generation of defective products caused by the buckling of a workpiece and also preventing the damage caused by overload on a robot gripper by eliminating a positioning error between the robot gripper and the workpiece and its apparatus.

(1) A ram 20 is started. When a punch P is brought into contact with the workpiece W which is gripped with the robot gripper 14 and after the workpiece W is released from the robot gripper 14, (2) the robot gripper 14 is made to follow the jumping-up action of the workpiece and, when the robot gripper 14 comes to the target angle position, it is made to stand by there. (3) After that, the ram 20 reaches the limit position and stops there and, after bending work is finished, the ram 20 is started in the reverse direction and, at the same time when the load of the workpiece becomes zero, the work piece W is gripped with the robot gripper 14 which is stood by at the target angle position.