An organic light emitting display device including a display panel including a first pixel connected with a first data line and first and second scan lines, a second pixel connected with a second data line and the first and second scan lines, and a reference line connected in common with the first and second pixels; a source driver configured to operate first and second sensing modes for sensing driving characteristic values of the first and second pixels through the reference line; and a scan driver configured to drive the first and second scan lines so as to drive only the first pixel for the first sensing mode or only the second pixel for the second sensing mode.