An organic light emitting display device is capable of securing sufficient compensation period such that a threshold voltage of a driving transistor may be compensated. A pixel includes: an organic light emitting diode; a second transistor for controlling an amount of current supplied from a first power source to the organic light emitting diode; a first capacitor having a first terminal coupled to a gate electrode of the second transistor; a first transistor coupled between a second terminal of the first capacitor and a data line, and being configured to turn on when a scan signal is supplied to a scan line; and a third transistor coupled between a gate electrode and a second electrode of the second transistor and having a turning-on period that is not overlapped with that of the first transistor. The third transistor is configured to turn on for a longer time than the first transistor.