ABSTRACT: Two novel polynorbornenes 1 and 2 funetionalized with electronically active conjugated oligomer units in the side chain were synthesized by the ring-opening metathesis polymerization (ROMP) method.Both polymers showed good optical characteristics, thermal stability, film-forming properties, and interesting electrochemical properties.The photophysieal and redox behaviors of 1 and 2 are markedly different due to variation in the structure of the pendant oligomers.Polymer 1 with phenyl end-capped oligothiophene cooligomer in the side chain showed much higher stability toward electrochemical oxidation than 2 with a sexithiophene in the side chain.