A backlight unit includes a substrate, a plurality of first light sources, a plurality of second light sources, a first wiring portion, a second wiring portion, a first connector and a second connector. The first light sources are disposed on the substrate. The second light sources are disposed on the substrate in a single line. The first wiring portion extends along a length direction on a first peripheral area of the substrate and is connected to the first light sources. The second wiring portion extends along the length direction on a second peripheral area of the substrate and is connected to the second light sources. The first connector is disposed on a first end portion of the substrate and is electrically connected to the first wiring portion. The second connector is disposed on a second end portion of the substrate and is electrically connected to the second wiring portion.