A light emitting diode including a light emitting structure including an active layer, a first distributed Bragg reflector (DBR) disposed on one side of the light emitting structure to reflect light emitted from the light emitting structure, and an interfacial layer disposed between the light emitting structure and the first DBR, in which the first DBR includes first material layers having a low refractive index and second material layers having a high refractive index alternately stacked one above another, the interfacial layer has a lower refractive index than the first material layers, and has a thickness greater than a thickness of each of the first and second material layers, and one a second material layer of the second material layers that is closest to the interfacial layer includes a first sub-layer and a second sub-layer, the first sub-layer having a density lower than that of the second sub-layer.