An organic light emitting display device includes a scan driving unit that supplies scan signals to scan lines, a data conversion unit that receives a first data signal for displaying an image and converts the first data signal to create a second data signal; a data driving unit that supplies the first data signal and the second data signal to data lines; a pixel unit including pixels positioned at intersections of the scan lines with the data lines, the pixels emitting light having a luminance corresponding to the first data signal during an image display subperiod and having a luminance corresponding to the second data signal during a compensation subperiod; and an image selection unit that transmits an image corresponding to the first data signal and blocking an image corresponding to the second data signal.