A light-emitting element includes a n-type silicon oxide film and a p-type silicon nitride film. The n-type silicon oxide film and the p-type silicon nitride film formed on the n-type silicon oxide film form a p-n junction. The n-type silicon oxide film includes a plurality of quantum dots composed of n-type Si while the p-type silicon nitride film includes a plurality of quantum dots composed of p-type Si. Light emission occurs from the boundary between the n-type silicon oxide film and the p-type silicon nitride film by injecting electrons from the n-type silicon oxide film side and holes from the p-type silicon nitride film side.