There are provided a circuit device for emitting heat to the outside and a backlight unit including the same. The present invention relates to a display device, a backlight unit connected to a display panel, or a constituent element thereof. The circuit device generates heat, and one or more heat emitting units for emitting heat generated from the light source of the backlight unit to the outside are added to the circuit device, and the backlight unit controlled by the aforementioned circuit device is provided. Each of the heat emitting units according to one embodiment of the present invention includes two or more different material layers to fix the circuit device and provide a heat emitting/directing function.