A semiconductor light emitting element, including: an n-type semiconductor layer having optical transparency with an emission wavelength of a light emitting layer, the light emitting layer and a p-type semiconductor layer, which are laminated; and a reflection film which is disposed on a side opposite to a surface from which light emitted from the light emitting layer is extracted, wherein the reflection film comprises: a transparent layer having optical transparency with the emission wavelength of the light emitting layer, and a metal layer, which is laminated on the transparent layer on a side opposite to the light emitting layer and is constituted by a metal material having a high reflectance, the transparent layer has a refractive index lower than a refractive index of a layer disposed on a side of the light emitting layer when viewed from the transparent layer, with the emission wavelength, and a thickness of the transparent layer is equal to or more than a value obtained by dividing a value of ¾ of the emission wavelength by the refractive index of the transparent layer.