A timing controller, a liquid crystal display (LCD) comprising the same and a driving method of the liquid crystal display, in which the LCD includes an LCD panel, a light source unit divided into n light-emitting blocks providing light to the LCD panel, a side member reflecting the light emitted from the light source unit, a timing controller determining a final brightness of each of the n light-emitting blocks and providing final light data corresponding to the final brightness, the final brightness being determined using reflected brightness based on the light reflected from the side member, and a backlight driver controlling the brightness of each of the n light-emitting blocks in response to the final light data.