An organic electroluminescent device is disclosed, comprising a substrate having thereon a light-emitting layer sandwiched by an anode and a cathode, wherein the light-emitting layer comprises at least: (1) a host material having electron-transporting or hole-transporting property, (2) Compound A capable of phosphorescence emission at room temperature, and (3) Compound B capable of phosphorescence emission or fluorescence emission at room temperature and having the maximum light emission wavelength longer than the maximum light emission wavelength of Compound A, and the maximum light emission wavelength of said device is attributable to said (3). The light emission attributable to (3) is intensified by (2) to elevate the light emission efficiency and by selecting a fluorescent compound as (3), the device can be prevented from aging deterioration of the luminance.