We report on the performance of a fabricated organic light-emitting device employing the electrophosphorescent material, fac tris(2-phenylpyridine) iridium (Ir(ppy)₃), doped into the new polyimide type of polymer, aromatic polyimide host. The luminance and the external quantum efficiency of the host emitter can be improved to ∼50000 cd m⁻² and ∼7, respectively, by doping the host with Ir(ppy)₃. The photoluminescence (PL) and electroluminescence (EL) have been investigated. The EL spectra shift with the changes of the concentration of Ir(ppy)₃. Bright green emission was observed from the EL devices. The current–voltage (I–V) characteristics suggest that, when the voltage is higher than the turn-on voltage, the current of the doped cell is higher than that of the undoped cell at the same voltage, indicating that the doping has an effect on the I–V characteristics.