Disclosed is an organic light-emitting element, comprising an organic light-emitting layer, a transparent substrate, and a transparent electrode disposed between the organic light-emitting layer and the transparent substrate; and which treats the surface of the transparent substrate on the opposite side from the transparent electrode as a light-extraction surface. The transparent substrate has birefringence, and has a configuration wherein the refraction index of a P polarized light is less than the refraction index of an S polarized light, improving the efficiency of light usage, where a polarized light in which an oscillation direction of an electrical field is parallel to a laminated surface of the organic light-emitting layer is designated S polarized light, and a polarized light that includes a vector of the direction of the progression of the light and in which the oscillation direction of the electrical field is included in a plane perpendicular to the laminated surface of the organic light-emitting layer is designated P polarized light.