PURPOSE: To apply work to a workpiece during its conveyance, by providing a work head, which applies the predetermined work to the workpiece held to a workpiece holding head having a degree of freedom of one axis or more, in a movable member supporting the workpiece holding head.

CONSTITUTION: A robot 1, which receives a workpiece W from the preceding robot, applies painting of a seal agent to the workpiece W, while it is conveyed, by a work head 6 of a work arm 5 in a condition that the workpiece W is held to a workpiece holding head 4. The neighboring robot, to which said workpiece W is delivered, applies the predetermined work to said workpiece W in a predetermined work station thereafter delivers the workpiece W to a robot and a machine device in the downstream side. In this way, the predetermined work can be applied by the work head 6 to the workpiece W while it is conveyed being held to the workpiece holding head 4 of the work robot 1.