An object of the present invention is to provide a backlight for a liquid crystal display device which is easy to repair and prevents the brightness from lowering on the screen, and thus can provide high-quality images, where the region where point light source elements are aligned is divided into a number of smaller regions, and backlight units are provided so as to correspond to the respective smaller regions, as well as a liquid crystal display device using the same. The present invention provides a backlight for a liquid crystal display device where a number of point light source elements 2 are aligned in a plane, having: a number of backlight units, each of which is formed of a support substrate 31, 32 for supporting point light source elements 2 and point light source elements 2 arranged on the support substrate, the region in which the point light source elements are aligned being divided into a number of smaller regions, each of which having a backlight unit; and a reflective sheet provided on the support substrates of the backlight units, having openings created at points where the point light source elements are located, characterized in that the reflective sheet is formed of a number of sheets 41, 42 and covers the entire region.