A high-luminance light emitting element is manufactured by a method comprising: forming a light emitting layer on a first surface of a GaP substrate including the first surface and a second surface opposed to the first surface and having an area smaller than the first area, the light emitting layer emitting light of a wavelength permitted to pass through the GaP substrate; forming a plurality of side surfaces on the GaP substrate to be respectively aslant by substantially the same angle to become narrower toward the second surface; and forming a plurality of depressions and protrusions as high as 0.1 to 3 on the side surfaces.