The present invention has an object to provide a method of raising a re-coupling efficiency of carriers in an EL element to thereby provide a light-emitting device having high emission efficiency. The method is that the electron trap region 106 and the hole trap region 107 are formed in the interior of the emission layer 103. The electron trap region 106 here is a region that has the action of enclosing within the emission layer an electrons that is transferred at the lowest unoccupied molecular orbit (LUMO) level of the emission layer 103. In addition, the hole trap region 107 is a region that has the action of enclosing within the emission layer a hole that is transferred at the highest occupied molecular orbit (HOMO) level of the emission layer 103.