A robot programming device, in which the teaching of the cooperative motion of a plurality of robots may be carried out in a short time so as to reduce the number of man-hours for starting-up a robot system including the robots. The robot system includes two handling robots each having a hand for gripping a workpiece and a welding robot having a welding torch, a robot controller for controlling the robots, a personal computer with a robot programming device connected to the controller, and a teaching operation panel connected to the controller for teaching each robot.