Disclosed is a light-emitting device including: a support member; and a light-emitting structure on the support member, the light-emitting structure including a first semiconductor layer, at least one intermediate layer, an active layer and a second semiconductor layer, wherein the intermediate layer is on at least one of upper and lower regions of the active layer and comprises at least four layers, wherein the layers have different band gaps, and wherein, among the layers, a layer having the largest band gap contacts a layer having the smallest band gap. Based on this configuration, it is possible to reduce crystal defects and improve brightness of the light-emitting device through effective diffusion of current.