An ultraviolet light emitting device comprises: a first substrate having a main surface; a second substrate facing the main surface of the first substrate; a gas in a space between the first substrate and the second substrate; electrodes directly or indirectly on the main surface of the first substrate; a dielectric layer that is located directly or indirectly on the main surface of the first substrate and covers the electrodes; and a first light-emitting layer. The first light-emitting layer is located directly or indirectly on the dielectric layer and emits ultraviolet light in the gas due to electrical discharge between the electrodes. The first light-emitting layer is thicker in first regions on the dielectric layer than in second regions. The second regions include at least part of regions directly above the electrodes.