A light-emitting device has a first light-emitting structure a second light-emitting structure on a top surface of the first light-emitting structure, an insulation layer between a top surface of the first light-emitting structure and a bottom surface of the second light-emitting structure; and a first electrode contacted with the second conductive type semiconductor layer and the third conductive type semiconductor layer. The first electrode contacts the insulation layer and the first electrode has a thickness thicker than that of the insulating layer.