A display device is provided. The display device includes a display panel, a backlight unit, and a luminance comparison unit. The backlight unit is configured to supply light to the display panel. The luminance comparison unit is configured to compare a measured luminance of the display panel with a reference luminance range. The backlight unit includes a light source unit, a DC-DC converter, and a driving current controller. The DC-DC converter is configured to supply a driving voltage to the light source unit, and the driving current controller is configured to control a driving current flowing to the light source unit based on the comparison result of the luminance comparison unit.