A liquid crystal display of a large screen size, a slim thickness and light weight is disclosed. The liquid crystal display includes a light supply unit group having at least two light guiding plates arranged in parallel and at least one lamp unit coupled to one side of the light guiding plate. A light control element is mounted on an upper surface of the light supply unit group, and uniformly controls luminance between the light guiding plate and the lamp unit. A reflective plate is disposed on a rear surface of the light supply unit group and has a shape corresponding to the rear surface of the light supply unit group. A back light assembly includes a receiving container that receives the light supply unit group, the light control element, and the reflective plate.