Provided is an organic light-emitting device in which light extraction efficiency for the luminescent color of each of organic light-emitting elements can be improved without an increase in driving voltage and a reduction in emission efficiency. The organic light-emitting elements for respective luminescent colors are different from each other in thickness of an electron injection layer, and the concentration of a metal or a metal compound in an electron injection layer is adapted to increase as the thickness of the electron injection layer decreases.