A dual display device comprises a first display panel, a second display panel and an adhesive. The first display panel comprises, in sequence, a first transparent substrate, a first electrode, a first organic functional layer and a second electrode. The second display panel comprises, in sequence, a second transparent substrate, a third electrode, a second organic functional layer and a fourth electrode. The second electrode and the fourth electrode are disposed opposite to each other. The adhesive seals the first transparent substrate and the second transparent substrate.