An aryldiamine compound represented by formula (1) and an organic electroluminescent device including a pair of electrodes and at least one organic layer disposed therebetween wherein the at least one organic layer contains the aryldiamine compound. The aryldiamine compound is excellent in hole transporting properties, hole injection properties, electron blocking properties, stability in thin film form, and heat resistance. The organic electroluminescent device achieves high emission efficiency and power efficiency, drives at a low voltage, and, in particular, has a long life.