In a liquid crystal display device according to the present invention, an upper end portion of a lamp housing is fixed on a main supporter so that the lamp housing can be made to face a side edge of a light guide. Light that can cause bright lines is eliminated or minimized through absorption or scattering by a main supporter. The main supporter is also thermally insulating and is placed between the lamp housing and a liquid crystal panel. Further, a thermally conducting bottom cover is placed under the backlight. Therefore, heat generated from the lamp is effectively channeled away from the light guide to prevent liquid crystal panel deterioration. Still further, although the upper and lower surfaces of the light guide is tightly fit between the lamp housing and the main supporter, wrinkles on a sheet reflector are prevented because the sheet reflector is not stacked between the lamp housing and a lower surface of the light guide.