A tandem OLED includes an anode, a cathode, and a plurality of organic electroluminescent units disposed between the anode and the cathode, wherein each organic electroluminescent unit includes at least one light-emitting layer, and an intermediate connector disposed between each adjacent organic electroluminescent unit, wherein the intermediate connector includes at least a high work function metal layer having a work function of no less than 4.0 eV and a metal compound layer, wherein the intermediate connector has a sheet resistance of higher than 100 kΩ per square, and wherein the high work function metal layer improves the operational stability of the OLED.