A liquid crystal display device includes a liquid crystal panel; a plurality of light emitting diode units to supply light to the liquid crystal panel; and a scan line and a light emission data line connected to the LED unit, wherein the scan line and the light emission data line transfer a scan signal and a light emission data current, respectively, wherein the LED unit includes: a switching circuit that is connected to the scan line and the light emission data line; a current mirror circuit that is connected to the switching circuit, and that outputs a light emission current in response to the light emission data current; and an LED that emits the light in response to the light emission current.