An organic light emitting display device that includes a plurality of signal lines and a plurality of scan lines, a plurality of pixels arranged at intersections of ones of the plurality of signal lines and ones of the plurality of scan lines, a scan driver to supply scan signals to the plurality of scan lines, the scan driver including a first plurality of thin film transistors and a data driver to supply data signals to the plurality of signal lines, the data driver including a second plurality of thin film transistors, wherein each of said plurality of pixels includes a first thin film transistor, a second thin film transistor and an organic light emitting diode, the first transistor being connected to the organic light emitting diode, the first transistor having an active layer made out of an oxide semiconductor, the second transistor, the first plurality of thin film transistors and the second plurality of thin film transistors each having an active layer made out of poly-silicon.