A backlight unit includes a light guide plate (LGP), one or more light-emitting devices disposed to face a side of the LGP and configured to generate light, a circuit board electrically connected to the one or more light-emitting devices, a quantum dot bar interposed between the LGP and the one or more light-emitting devices and configured to convert a wavelength of light, and a housing configured to house the one or more light-emitting devices, the circuit board and the quantum dot bar, and comprising first and second open end portions and an open side portion through which a portion of the LGP is inserted. The backlight unit further includes first and second covers covering the first and second open end portions of the housing, respectively, and coupled to the housing. The first cover and the second cover respectively include a first coupling portion and a second coupling portion which are coupled to first and second ends of the quantum dot bar, respectively.