A display device includes a folding region, and a non-folding region which is adjacent to the folding region along a first direction, a display module which displays an image, a window on the display module, a lower support plate facing the window with the display module therebetween, the lower support plate including a metal material, and an upper support plate between the display module and the lower support plate. The upper support plate includes a support layer including glass fiber and a polymer material, a first surface including a first concave-convex pattern, and a second surface opposite to the first surface, closer to the display module than the first surface and including a second concave-convex pattern and a metal layer directly on the first surface of the support layer, in the non-folding region.