A light emitting device comprises a light emitting element having a first electrode and a second electrode, and a semiconductor member having a cavity in a principal surface thereof, inside which the light emitting element is mounted, and electrically connected to the light emitting element, wherein the semiconductor member is constructed as a voltage regulating diode for stabilizing a voltage supplied from the exterior. As a result, the light emitting element can be protected from a static electricity or a surge voltage flowed therein from the exterior, the entire size of the system can be remarkably reduced so as to simplify a structure thereof, and heat generated from the system can be effectively discharged to the exterior. In addition, by providing a reflection portion in the cavity, light emitted from the light emitting element can be efficiently condensed.