An organic light emitting display device may include a plurality of pixels, a plurality of scan lines for selectively applying a scan signal to the pixels, a plurality of data lines crossing the scan lines for applying a data signal to the respective pixels, a scan driver for applying a scan signal to the scan lines, and at least one first testing unit electrically connected to the scan driver, wherein at least one output line of the first testing unit is electrically connected to the scan driver, and at least one other output line of the first testing unit is electrically disconnected and in an electrically open state.