A display device includes: a light guide member under the display panel and including a light incident surface; a heat discharge member including a heat discharge surface which extends in a first direction opposite to the light incident surface of the light guide member, and a first flat surface which extends in a second direction from the heat discharge surface; and a light source on the heat discharge member, which provides light to the light incident surface and includes a light emitting device on the heat discharge surface and including a light emitting surface opposite to the light incident surface, a circuit board on the first flat surface of the heat discharge member and electrically connected to the light emitting device, and a heat discharge portion on the heat discharge member and which couples the light emitting device to the heat discharge surface of the heat discharge member and discharges a heat generated from the light emitting device.