An LED backlight in which deterioration in in-plane uniformity of brightness is prevented, whose thickness, frame width, and wire length are reduced, and in which wiring can be carried out easily, includes an LED provided on one surface of an LED substrate; the LED substrate is mounted on a chassis panel so that a surface of the LED substrate opposite to the one surface contacts the chassis panel; and the chassis panel has a connection hole provided in a portion of a region of the chassis panel in which region the LED substrate is mounted, which passes through the chassis panel.