The invention discloses a double-layer laminating unit which comprises an electromagnetic plate splitting device and a double-layer laminating machine, wherein the double-layer laminating machine is positioned on the downstream side of the electromagnetic plate splitting device; the electromagnetic plate splitting device comprises a portal frame; the portal frame is provided with a conveying roller bed and an electromagnetic chuck; the double-layer laminating machine comprises a base; a laminating seat is arranged on the base; a lifting rack driven by a power device is arranged on the laminating seat; an upper laminating roller is arranged on the lifting rack; a lower laminating roller is arranged below the upper laminating roller; an upper film placement device is connected to the laminating seat; a lower film placement device is arranged on the lower part of the base; a film cutting device is arranged on the upstream side of the laminating seat; and an induction switch is arranged on the upstream side of the film cutting device. According to the double-layer laminating unit disclosed by the invention, the compound surface of the lower compound plate is laminated by the upper laminating device; and after laminating is completed, the film is cut off by the film cutting device, the upper compound plate is put down, the compound surface of the upper compound plate is laminated by the lower laminating device, an online laminating function is realized, the processing efficiency is improved, and the production cost is reduced.