A display device includes a display panel, a light source unit, a light guide plate including a light exit surface, a bottom surface, a light incident surface, an opposite surface, and first and second side surfaces connecting the light incident surface and the opposite surface and being opposite to each other, a first refractive layer disposed on the light exit surface and having a refractive index lower than that of the light guide plate, an optical member between the display panel and the light guide plate, and an protective member covering at least one of a side surface of the optical member and at least a portion of a side surface of the light guide plate corresponding thereto.