| abstract |
The present specification relates to an organic light emitting device comprising a first electrode, a second electrode, and one or more organic material layers provided between the first electrode and the second electrode, wherein one or more layers of the organic material layers comprise a heterocyclic compound represented by Chemical Formula 1 and a heterocyclic compound represented by Chemical Formula 2 at the same time, and a composition for an organic material layer of an organic light emitting device. |