A field emission backlight for a display device includes upper and lower substrates. The upper substrate includes an upper transparent substrate, a transparent electrode, and a fluorescent part. The lower substrate includes a lower transparent substrate having a receiving groove, a first electrode part, a second electrode part, and an electron-emitting part. The first electrode part is formed on an upper surface of the lower transparent substrate and the second electrode part is formed on a bottom surface of the receiving groove, so that the gap between the first and second electrode parts can be reduced below that conventionally required. This, in turn, enables the level of a voltage applied between the first and the second electrode parts to be reduced, and a corresponding reduction in the manufacturing cost of a field emission backlight to be achieved.