A pixel and an organic light emitting display using the same are provided. The display displays an image having desired gray levels while allowing the voltage of data signals to be reduced. The pixel includes an organic light emitting diode; a driving transistor for supplying a current to the organic light emitting diode; a switching transistor configured to supply a data signal from a data line to a gate electrode of the driving transistor based on a scan signal from a scan line; a storage capacitor coupled between the gate electrode of the driving transistor and a source electrode of the driving transistor; and an initialization transistor coupled between the source electrode of the driving transistor and an initialization power voltage.