An exemplary liquid crystal display device includes a backlight module, a metallic bracket and a liquid crystal panel. The backlight module includes a back bezel, a planar lighting source mounted on the back bezel and a frame. The frame includes a metallic beam and three plastic beams. The metallic beam and the plastic beams enclose the back bezel. The metallic beam is located at a top of the liquid crystal display device. The metallic bracket supports the backlight module and thermally connects with the metallic beam of the frame of the backlight module. The liquid crystal panel is located at a surface of emission of the planar lighting source.