An error compensator and an organic light emitting display device using the same. The organic light emitting display device includes pixels each having a driving transistor and an organic light emitting diode; and a sensing unit extracting at least one of a first information including the threshold voltage of the driving transistor or a second information including the degradation of the organic light emitting diode from a pixel of the pixels. In the organic light emitting display device, the sensing unit includes an amplifier amplifying a voltage corresponding to the at least one of the first information or the second information; and an error compensator compensating for error components of elements included in the amplifier and the error compensator.