A semiconductor light emitting device including a first conductive electrode and a second conductive electrode; a first conductive semiconductor layer on which the first conductive electrode is disposed; a second conductive semiconductor layer overlapping the first conductive semiconductor layer, on which the second conductive electrode is disposed; and an active layer disposed between the first conductive semiconductor layer and the second conductive semiconductor layer. Further, the second conductive semiconductor layer includes a first layer including a porous material capable of being electro-polished and disposed on an outer surface of the semiconductor light emitting device; a second layer disposed under the first layer and having a lower impurity concentration than the first layer; and a third layer disposed between the second layer and the active layer and having a higher impurity concentration than the second layer.