Electrochemical and electroluminescent (EL) properties of a polymer liquid crystal (PLC) composed of an oxadiazole moiety as an electron-transporting unit and an amine moiety as a hole-transporting unit in the same side chain were investigated. It has been found that the polymer is a good candidate for a single-layer light-emitting diode (LED) because it combines carrier-transporting and emission properties in a single species. A polymer LED was fabricated with a simple configuration of ITO/PLC/MgAg to demonstrate EL behavior. The device showed the EL emission in a blue region with a maximum brightness of 13 cd/m(2) at 26 V. Furthermore, a polarized EL emission was observed due to self-assemblies of mesogenic chromophores. The dichroic ratio of the absorption of the polymer film determined by polarized absorption spectra measured with the polarized beam parallel and perpendicular to the rubbing direction was 1.8, and the dichroic ratio of the emission was estimated to be 1.6. These results clearly indicate that the origin of the polarized emission from the polymer film is the anisotropic arrangement of the mesogenic chromophores.