To provide a light-emitting device with a heat radiating structure in which inside heat can be efficiently discharged without increasing a thickness and provide a display device in which contrast characteristics of a screen can be improved and excellent display quality can be realized by using the above light-emitting device in a backlight unit.

The light-emitting device is provided with a first substrate 12 as well as a second substrate 14 which are arranged to face each other and form a vacuum container, an electron emission unit 110 formed on an inner surface of the first substrate, a light-emitting unit 120 formed on an inner surface of the second substrate, and a heat conductive medium 32 which is arranged inside the vacuum container to absorb and discharge heat, and the second substrate 14 is divided into an effective region (A) where light is emitted by the light-emitting unit and a non-effective region (NA) which is arranged in outer edges of the effective region (A), and the heat conductive medium 32 is formed on a side of the non-effective region (NA).