A dual display device includes a light source module, a first display panel and a second display panel. The light source module includes a light guide plate, a first prism sheet, a second prism sheet, a color conversion film, and a light source. The light guide plate has a first light exit surface, a second light exit surface and a light incident surface. The first light exit surface has a plurality of first microstructures. The first prism sheet is disposed beside the first light exit surface. The second prism sheet is disposed beside the second light exit surface. The color conversion film is disposed at least one of between the first prism sheet and the first light exit surface and between the second prism sheet and the second light exit surface. The dual display device of the invention has the advantages of thinner thickness and lighter weight.