Provided is a semiconductor light emitting device. The semiconductor light emitting device comprises a first conductive type semiconductor layer, an active layer, and a second conductive type semiconductor layer. The active layer comprises a first active layer, a second active layer, an electron barrier layer on the first conductive type semiconductor layer. The first active layer and the second active layer comprise a quantum well layer and a quantum barrier layer. The electron barrier layer is formed between the first active layer and the second active layer. The second conductive type semiconductor layer is formed on the active layer.