An organic light emitting diode includes a hole injection layer, a hole transport layer, an optical compensation layer, an emission layer, an electron transport layer and an electron injection layer. The optical compensation layer is disposed on the hole transport layer and includes a phosphorescent host material. Thus, an electron barrier on an interface between the optical compensation layer and an emission layer may be reduced. Thus, the luminance efficiency in a low gray scale area may be decreased, and the stain and roll-off phenomenon in the low gray scale area may be improved.