A display device includes a first non-foldable area, a second non-foldable area, and a foldable area. The display device includes a display module including a display panel, a support substrate supporting the display module, including an upper surface facing the display module and a lower surface opposite to the upper surface, and provided with a groove defined in the lower surface to overlap the foldable area, a first support plate disposed under the support substrate, and a second support plate disposed under the support substrate and spaced apart from the first support plate in the foldable area.