A backlight unit includes a light source part configured to emit a light and a reflective sheet disposed under the light source part. The light source part includes a first light source block including a plurality of light sources with first distances therebetween and a second light source block including a plurality of light sources with second distances therebetween. The first distances increase or decrease as the light sources of the first light source block are closer to an end portion of the first light source block than to a center portion of the first light source block, and the second distances increase as the light sources of the second light source block axe closer to an end portion of the second light source block than to a center portion of the second light source block.