A light emitting diode comprising: a first light emitting structure comprising a first conductivity type first semiconductor layer, a first active layer under the first conductivity type first semiconductor layer, and a second conductivity type second semiconductor layer under the first active layer; a first reflective electrode under the first light emitting structure; a second light emitting structure adjacent to the first light emitting structure and comprising a first conductivity type third semiconductor layer, a second active layer under the first conductivity type third semiconductor layer, and a second conductivity type fourth semiconductor layer under the second active layer; a second reflective electrode under the second light emitting structure; a contact part that electrically connects the first conductivity type first semiconductor layer of the first light emitting structure to the second reflective electrode; a first insulating layer between the contact part and the second conductivity type second semiconductor layer; and, a conductive support substrate under the first and second light emitting structures (10; 20), wherein the contact part makes contact with an inner portion of the first conductivity type first semiconductor layer, the contact part directly contacts a lower portion and a lateral side of the second reflective electrode, characterized in that, the first insulating layer is an ion implantation layer, the light emitting device further comprises a second insulating ion implantation layer between the contact part and the first conductivity type third semiconductor layer, and the second insulating ion implantation layer having a line width less than several tens of micrometers is disposed between the first light emitting structure and the second light emitting structure. a first light emitting structure comprising a first conductivity type first semiconductor layer, a first active layer under the first conductivity type first semiconductor layer, and a second conductivity type second semiconductor layer under the first active layer; a first reflective electrode under the first light emitting structure; a second light emitting structure adjacent to the first light emitting structure and comprising a first conductivity type third semiconductor layer, a second active layer under the first conductivity type third semiconductor layer, and a second conductivity type fourth semiconductor layer under the second active layer; a second reflective electrode under the second light emitting structure; a contact part that electrically connects the first conductivity type first semiconductor layer of the first light emitting structure to the second reflective electrode; a first insulating layer between the contact part and the second conductivity type second semiconductor layer; and, a conductive support substrate under the first and second light emitting structures (10; 20), wherein the contact part makes contact with an inner portion of the first conductivity type first semiconductor layer, the contact part directly contacts a lower portion and a lateral side of the second reflective electrode, characterized in that, the first insulating layer is an ion implantation layer, the light emitting device further comprises a second insulating ion implantation layer between the contact part and the first conductivity type third semiconductor layer, and the second insulating ion implantation layer having a line width less than several tens of micrometers is disposed between the first light emitting structure and the second light emitting structure.