An organic light-emitting device is provided. The organic light-emitting device includes: an anode; a cathode; and an organic layer between the anode and the cathode and including an emission layer, wherein the emission layer includes a first emission layer including a first host, a second host, and a first dopant, and a second emission layer including a third host, a fourth host, and a second dopant, and the organic light-emitting device satisfies Equations 1 and 2.