A light emitting device comprising: a light emitting structure comprising a first semiconductor layer , a second semiconductor layer , and an active layer between the first and second semiconductor layers; a first electrode electrically connected to the first semiconductor layer ; and a second electrode disposed over the second semiconductor layer , wherein the second electrode comprises: a reflective electrode layer disposed over the second semiconductor layer ; and a bonding electrode layer disposed in at least a partial region of an outer side surface of the reflective electrode layer while coming into contact with the second semiconductor layer , wherein the bonding electrode layer has a structure in which a chromium (Cr) layer (188-1), an aluminum (Al) layer (188-2), a nickel (Ni) layer (188-3), and a gold (Au) layer (188-4) are laminated in this order, wherein the chromium layer is disposed to come into contact with the upper surface of the second semiconductor layer , wherein said reflective electrode layer of said second electrode comprises a structure in which at least a first aluminum (Al) layer (182-1), a first nickel (Ni) layer (182-2), and a first gold (Au) (182-3) layer are laminated in this order, and wherein first Al layer (182-1) is disposed to come into contact with an upper surface of said second semiconductor layer . a light emitting structure comprising a first semiconductor layer , a second semiconductor layer , and an active layer between the first and second semiconductor layers; a first electrode electrically connected to the first semiconductor layer ; and a second electrode disposed over the second semiconductor layer , wherein the second electrode comprises: a reflective electrode layer disposed over the second semiconductor layer ; and a bonding electrode layer disposed in at least a partial region of an outer side surface of the reflective electrode layer while coming into contact with the second semiconductor layer , wherein the bonding electrode layer has a structure in which a chromium (Cr) layer (188-1), an aluminum (Al) layer (188-2), a nickel (Ni) layer (188-3), and a gold (Au) layer (188-4) are laminated in this order, wherein the chromium layer is disposed to come into contact with the upper surface of the second semiconductor layer , wherein said reflective electrode layer of said second electrode comprises a structure in which at least a first aluminum (Al) layer (182-1), a first nickel (Ni) layer (182-2), and a first gold (Au) (182-3) layer are laminated in this order, and wherein first Al layer (182-1) is disposed to come into contact with an upper surface of said second semiconductor layer . a reflective electrode layer disposed over the second semiconductor layer ; and a bonding electrode layer disposed in at least a partial region of an outer side surface of the reflective electrode layer while coming into contact with the second semiconductor layer , wherein the bonding electrode layer has a structure in which a chromium (Cr) layer (188-1), an aluminum (Al) layer (188-2), a nickel (Ni) layer (188-3), and a gold (Au) layer (188-4) are laminated in this order, wherein the chromium layer is disposed to come into contact with the upper surface of the second semiconductor layer , wherein said reflective electrode layer of said second electrode comprises a structure in which at least a first aluminum (Al) layer (182-1), a first nickel (Ni) layer (182-2), and a first gold (Au) (182-3) layer are laminated in this order, and wherein first Al layer (182-1) is disposed to come into contact with an upper surface of said second semiconductor layer . <EOS>