A pixel of an organic light emitting display device and an organic light emitting display device using the same. The pixel is configured to compensate for the deterioration of organic light emitting diodes. The pixel includes an organic light emitting diode; a pixel circuit including a drive transistor for controlling an amount of electric current that flows from a first power source to a second power source via an organic light emitting diode; and a compensation unit between a gate electrode and a first electrode of the drive transistor for controlling a voltage of the gate electrode of the drive transistor to correspond to the deterioration of the organic light emitting diode. The compensation unit includes a transistor and a capacitor coupled in series between the gate electrode and the first electrode of the drive transistor.