A display device includes a substrate including a display area and a first surface and a second surface opposite each other; and pixels in the display area and including an emission area and a non-emission area, respectively. Each of the pixels may include: a pixel circuit layer including one or more transistors on the first surface of the substrate in the non-emission area, and a first insulating layer, a second insulating layer, a third insulating layer and a fourth insulating layers that are sequentially stacked on the first surface of the substrate and respectively include an opening exposing the first surface of the substrate in the emission area; an optical layer on the pixel circuit layer; and a light emitting element layer on the optical layer. The optical layer may fill the opening of each of the first to fourth insulating layers in at least the emission area.