A new class of novel high-efficiency light-emitting nitrogen-containing PPV-related copolymers which have hole transfer moieties such as triphenylamine (TPA) and alkyl-carbazole units and conjugated aromatic units such as 4,4'-biphenylene, 1.4-phenylene, 1,4- or 1,5 naphthylene and 9,10-anthrylene, was designed and synthesized by the well-known Wittig-Hornor reaction. The optical and electrical properties were examined. The resulting alternating copolymers were highly soluble in common organic solvents, with good film-forming properties and high fluorescence quantum yields and also emit blue/green lights when used as the active layer of LEDs.