An illuminating apparatus for improving brightness of light, a backlight assembly and an LCD device having the same are provided. The LCD device includes a backlight unit having a lamp for emitting a first light, a light guiding plate for guiding the first light, and a lamp reflector disposed adjacent to the lamp to partially cover the lamp and receiving the first light exited from the lamp, the lamp reflector having a plurality of protrusion portions for diffusing and reflecting the received first light to generate a second light; and a display unit for displaying images in response to the second light, the display unit having a lower substrate, an upper substrate opposite to the lower substrate, and a liquid crystal layer disposed between the lower and the upper substrates.