A semiconductor light emitting device includes a laminate section in which p-type layer 5 and n-type layer 7 are laminated such that they sandwich active layer 6. A part of light emitted from active layer 6 exits from a first surface of the laminate section. The semiconductor light emitting device includes a reflection layer that is located on a second surface opposite to the first surface of the laminate section and that reflects light that is emitted from active layer 6 and that enters from the second surface in the direction of the active layer side. The reflection layer includes metal layer 1 and transparent electrode films 2 to 4 that are transparent to a wave length of light that enters from active layer 6 and that have conductivity. The refractive index of transparent conduction film 3 is lower than that of each of transparent conduction films 2 and 4 and p-type layer 5. The absorption coefficient of transparent conduction film 3 is smaller than that of each of transparent conduction films 2 and 4.