Disclosed is a liquid crystal display device wherein display performance of a two-dimensional image and that of a three-dimensional image are both improved. The liquid crystal display device is provided with: a liquid crystal display panel, which displays the two-dimensional image and the three-dimensional image by selectively switching the images; and a backlight, which supplies light to the liquid crystal display panel. The backlight includes an illuminating region, which is scan-lighted corresponding to scanning of the liquid crystal display panel, and the scanning frequencies of the illuminating region at the time of displaying the two-dimensional image and the three-dimensional image on the liquid crystal display panel are different from each other.