Derivatives of benzo[h]naphtho[1,2-f]quinoline and organic light emitting devices (OLEDs) including them are disclosed. The subject compounds impart high efficiency, low driving voltage, high luminance and long lifespan to the OLEDs. The subject compounds may be used as light emitting materials, as electron transporting materials, or as electron injecting materials. Because the subject compounds have high glass transition temperatures or high melting points, OLEDs including them exhibit high durability in storage or operation. Suitable substituents may be selected from deuterium, alkyl, alkenyl, alkynyl, cycloalkyl, alkoxy, aryloxy, arylthio, aryl, aryl- or heteroaryl-substituted amino, heteroaryl, condensed polycyclic, halogen, cyano, nitro, hydroxyl and carboxyl groups.