The nitride-based light emitting device according to one embodiment includes a first nitride semiconductor layer doped with a first conductive impurity; a strain buffer layer formed on the first nitride semiconductor layer and comprised of InGaN; an active layer formed on the strain buffer layer and having a multi-quantum well structure in which a quantum-well layer and a quantum-barrier layer are alternately stacked one above another; and a second nitride semiconductor layer formed on the active layer and doped with a second conductive impurity opposite to the first conductive impurity, wherein the ratio B/A satisfies 1.4