To improve stability of a device by adjusting electrical conductance of an electron source and a light emitting region.

This organic light emitting device (OLED) 400a includes a positive electrode 402, a hole source 403, the light emitting region 404, the electron source 405 and a negative electrode 406. Materials of the electron source and the hole source are so selected that each of the electrical conductance is larger than that of the light emitting region. Especially, the of the electrical conductance of the electron source and the hole source are desirably 10-8 to 102 S/cm. In addition to this, at least one of the electron source and the hole source basically includes one or many of inorganic materials, and the light emitting region includes one or many of organic material layers. The material of the light emitting region is constituted by an insulator. The negative electrode is constituted by, for example, metals of Mg:Ag and/or Al, etc. The positive electrode is constituted by a transparent conductive substance such as an ITO, etc. The electrical conductance of the negative electrode and the positive electrode are 102 S/cm or above.