An organic light emitting display device includes: a scan driver for driving one or more scan lines and emission control lines; a data driver for sequentially providing j data signals to each of a plurality of output lines in each horizontal period; a demultiplexer for transmitting the j data signals to j first data lines, the demultiplexer being coupled to the output lines; a plurality of pixels at crossing regions of the scan lines and second data lines extending in a direction crossing the scan lines; and a common circuit unit for controlling voltages of the second data lines coupled to the pixels by using a reference voltage and an initial voltage and the data signals, the common circuit unit being coupled between the first data lines and the second data lines.