A method for driving an organic light emitting display according to an embodiment includes applying an initial value of a high potential driving power and a test pattern to a display panel and sensing changes in driving characteristics of the display panel while varying a voltage level of the high potential driving power from the initial value, deciding whether or not a sensed driving characteristic value of the display panel satisfies a predetermined condition, setting a voltage level of the high potential driving power obtained when the sensed driving characteristic value satisfies the predetermined condition, as a reference value of the high potential driving power, and adding a voltage margin to the reference value of the high potential driving power to determine a final value of the high potential driving power, and driving the display panel using the final value of the high potential driving power.