A light-emitting device includes a substrate; a first light-emitting unit and a second light-emitting unit formed on the substrate, each of the first light-emitting unit and the second light-emitting unit includes a first semiconductor layer, a second semiconductor layer, and an active layer between the first semiconductor layer and the second semiconductor layer; a trench formed between the first light-emitting unit and the second light-emitting unit, and exposing the substrate; and a connecting electrode including a first connecting part on the first light-emitting unit and connected to the first semiconductor layer of the first light-emitting unit, a second connecting part on the second light-emitting unit and connected to the second semiconductor layer of the second light-emitting unit, and a third connecting part formed in the trench to connect the first connecting part and the second connecting part.