A backlight unit using optical fibers includes a light source, an optical medium tube having a light incident surface to optically couple light from the light source into the optical medium tube and a light emitting surface to emit light guided by the optical medium tube, a light emitting plate including plurality of optical fibers having first ends optically coupled to the light emitting surface of the optical medium tube to receive light from the light emitting surface, where the first ends of the optical fibers are substantially parallel and coplanar with each other.