An organic light-emitting device includes a first electrode; a second electrode facing the first electrode; and an organic layer between the first electrode and the second electrode and including an emission layer. The organic layer includes at least one of an amine-based compound represented by Formula 1, for example, in the hole transport region, hole transport layer, or emission layer. The organic light-emitting device including the amine-based compound represented by Formula 1 may exhibit improved driving voltage, efficiency, and excellent I-V-L characteristics: