Disclosed is a light emitting device including a plurality of light emitting cells disposed on a substrate, at least one connection electrode for connecting the light emitting cells, and a first insulating layer disposed between adjacent light emitting cells, wherein each of the light emitting cells includes a light emitting structure including first and second conductive type semiconductor layers and an active layer, and a reflective layer disposed on the second conductive type semiconductor layer, wherein the connection electrode connects the first conductive type semiconductor layer of a first one of the adjacent light emitting cells to the reflective layer of a second one at the adjacent light emitting cells, and wherein a first width of the second conductive type semiconductor layer is the same as or greater than a second width of the reflective layer, and the first direction differs from a thickness direction of the light emitting structure.