Display device and bottom chassis thereof

The display device and the bottom chassis are provided. Display device of the present invention at least one optical member coupled to the opening in order to improve the optical properties of the emitted light from the bottom chassis (Bottom Chassis), and the light source to an opening provided and on a side receiving the light source therein a display device comprising, characterized in that it comprises an optical unit for the stock includes a position guide portion protruding from the bottom chassis to derive the optical material in place.