A display device includes a touch panel, a display panel, a backlight assembly, a bottom chassis, and a rear cover. The display panel is coupled to the touch panel. The backlight assembly includes a light source to supply light to the display panel, and an optical sheet including a protrusion. The display panel is disposed between the touch panel and the backlight assembly. The bottom chassis includes extensions protruding from walls defining a cavity region to receive the display panel. The extensions support the touch panel. The rear cover is configured to receive the bottom chassis. The bottom chassis is disposed between the rear cover and the touch panel. One of the walls of the bottom chassis includes an opening. The protrusion is configured to engage the opening to couple the optical sheet to the bottom chassis.