A coil module includes a first coil set; a second coil set, including a first coil body, a second coil body and an insulative separator disposed between the first coil body and the second coil body, the separator having an adopting hole, the first coil body having an open winding surrounding the adapting hole and fixed on a side of the separator, the second coil body having an open winding surrounding the adapting hole and fixed on another side of the separator; and a coil base sheathing the second coil set with exposing the adopting hole. The first coil set surrounds the adopting hole and is fixed on the coil base to form a coil module.