Abstract: Manufacturing a coil with high precision and high efficiency. Device for manufacturing a coil 3 by welding U-shaped pipes 2 at both ends of a plurality of straight pipes 1. Providing a laser welding head 11 which uses a condensing lens 15 having a focal length at least twice the diameter of the pipes 1, 2 to be welded, to perform welding by irradiating a laser light 13 onto the straight pipes 1 held in position by a workpiece setting jig 24, and onto a joint position w of U-shaped pipes 2 which are temporarily fitted to both ends of the straight pipes 1. Making it possible to manufacture a coil with high precision and high efficiency, without using a filler wire.