A semiconductor light-emitting device includes a substrate; a first cladding layer formed on the substrate; a first guide layer formed on the first cladding layer; an active layer formed on the first guide layer; a second guide layer formed on the active layer; a contact layer formed on the second guide layer; a cladding electrode formed on the contact layer, and made of conductive metal oxide; and a pad electrode electrically coupled to the cladding electrode. The semiconductor light-emitting device includes a mesa structure including the contact layer. The cladding electrode has a greater width than the mesa structure. The cladding electrode covers an upper surface and side surfaces of the mesa structure, and is electrically coupled to the contact layer.