A semiconductor light emitting element comprising: a substrate; and an n-side semiconductor layer stacked on the substrate; an active layer stacked on the n-side semiconductor layer; and a p-side semiconductor layer stacked on the active layer, the active layer having a multiple quantum well structure including a plurality of barrier layers and a plurality of well layers adjacent to the barrier layers, and among the barrier layers, a final barrier layer disposed closest to the p-side semiconductor layer and a plurality of barrier layers adjacent to the final barrier laye via a well layer, respectively, on a side close to the p-side semiconductor layer, each having a greater thickness than a thickness of a barrier layer disposed on a side close to the n-side semiconductor layer, wherein the well layers are made of an undoped InGaN and the barrier layers are made of an undoped nitride semiconductor having a larger band gap energy than the well layers, characterised in that the barrier layers in the active layer include: the barrier layer disposed on a side close to the n-side semiconductor layer; a plurality of barrier layers having a same thickness as the barrier layer disposed on a side close to the n-side semiconductor layer, and adjacent to the barrier layer disposed on a side close to the n-side semiconductor layer via a well layer, respectively; -the final barrier layer disposed closest to the p-side semiconductor layer; and -a plurality of barrier layers having a same thickness as the final barrier layer, and adjacent to the final barrier layer via a well layer, respectively, wherein a number of the barrier layers disposed on the side close to the n-side semiconductor layer and having the same thickness with each other is greater than a number of the barrier layers disposed on the side close to the p-side semiconductor layer and having the same thickness with each other. a substrate; and an n-side semiconductor layer stacked on the substrate; an active layer stacked on the n-side semiconductor layer; and a p-side semiconductor layer stacked on the active layer, the active layer having a multiple quantum well structure including a plurality of barrier layers and a plurality of well layers adjacent to the barrier layers, and among the barrier layers, a final barrier layer disposed closest to the p-side semiconductor layer and a plurality of barrier layers adjacent to the final barrier laye via a well layer, respectively, on a side close to the p-side semiconductor layer, each having a greater thickness than a thickness of a barrier layer disposed on a side close to the n-side semiconductor layer, wherein the well layers are made of an undoped InGaN and the barrier layers are made of an undoped nitride semiconductor having a larger band gap energy than the well layers, characterised in that the barrier layers in the active layer include: the barrier layer disposed on a side close to the n-side semiconductor layer; a plurality of barrier layers having a same thickness as the barrier layer disposed on a side close to the n-side semiconductor layer, and adjacent to the barrier layer disposed on a side close to the n-side semiconductor layer via a well layer, respectively; -the final barrier layer disposed closest to the p-side semiconductor layer; and -a plurality of barrier layers having a same thickness as the final barrier layer, and adjacent to the final barrier layer via a well layer, respectively, the barrier layer disposed on a side close to the n-side semiconductor layer; a plurality of barrier layers having a same thickness as the barrier layer disposed on a side close to the n-side semiconductor layer, and adjacent to the barrier layer disposed on a side close to the n-side semiconductor layer via a well layer, respectively; -the final barrier layer disposed closest to the p-side semiconductor layer; and -a plurality of barrier layers having a same thickness as the final barrier layer, and adjacent to the final barrier layer via a well layer, respectively, wherein a number of the barrier layers disposed on the side close to the n-side semiconductor layer and having the same thickness with each other is greater than a number of the barrier layers disposed on the side close to the p-side semiconductor layer and having the same thickness with each other.