An organic light emitting device is disclosed. The organic light emitting device includes a substrate, a display unit that is positioned on the substrate and includes a subpixel and a monitor pixel, a first line supplying a voltage to the subpixel and the monitor pixel, a second line supplying a direct current (DC) power to the monitor pixel, a third line that transfers an electrical signal used to display an image on the subpixel, and a shield layer that is positioned on or under the second line and is electrically connected to the first line.