Abstract: A nitride-semiconductor light-emitting element includes an n-type nitride-semiconductor layer, a p-type nitride-semiconductor layer, and a light-emitting layer between the n-type nitride-semiconductor layer and the p-type nitride-semiconductor layer. The light-emitting layer has one or more quantum well layers and two or more barrier layers between which the quantum well layer(s) lie. A first barrier layer, which is the closest of the two or more barrier layers to the p-type nitride-semiconductor layer, has a thickness equal to or smaller than that of the barrier layer(s) different from the first. There is an undoped layer, a layer of a nitride semiconductor represented by a general formula AlsGatInuN (0<s<1, 0<t<1, 0?u<1, and s+t+u=1), between the first barrier layer and the p-type nitride-semiconductor layer.