A cascaded organic electroluminescent device includes an anode, a cathode, and a plurality of organic electroluminescent units disposed between the anode and the cathode, wherein the organic electroluminescent units comprise at least a hole-transporting layer and an electron-transporting layer. The device also includes a connecting unit disposed between each adjacent organic electroluminescent unit, wherein the connecting unit comprises, in sequence, an n-type doped organic layer, and a p-type doped organic layer wherein the p-type doped organic layer includes a dihydrophenazine derivative compound.