A backlight unit includes a light source, a light guiding plate disposed on a side of the light source to guide light, a quantum dot bar disposed between the light source and the light guiding plate and spaced apart from the light source and the light guiding plate, the quantum dot bar for performing wavelength conversion of light, and a quantum dot bar receiving unit disposed on lower surfaces of the quantum dot bar and the light guiding plate, wherein the quantum dot bar is seated on the quantum dot bar receiving unit, and the light guiding plate is mounted on the quantum dot bar receiving unit, and wherein the quantum dot bar receiving unit and the light guiding plate are coupled to each other.