An organic electro-luminescent device. The device comprises two electrodes and an organic electro-luminescent structure interposed therebetween. The electrodes are disposed on a substrate, one serving as an anode and the other as a cathode. The organic electro-luminescent structure comprises a fluorescent emissive layer, a phosphorescent emissive layer and a nondoped organic material layer interposed therebetween. The phosphorescent emissive layer has a host material. The nondoped organic material layer has a highest occupied molecular orbital (HOMO) energy level no higher than that of the host material in the phosphorescent emissive layer.