Two new cyano-substituted copolymers containing biphenylenevinylene and bithienylenevinylene moieties (DCN-PPV and DCN-PTV) were synthesized by a stille condensation reaction with Pd(PPh3)(4) as catalyst. Their structures were confirmed by H-1 NMR, IR spectroscopy, and elemental analysis. The thermal, optical, and electrochemical properties of the polymers were investigated. The results show that the polymers possess high thermal decomposition temperature and reversible n-doping/dedoping processes. In addition, DCN-PTV has higher electron affinity with a low LUMO energy level of -3.84 eV and a relatively broader absorption band covering 300-780 nm, indicating that DCN-PTV could be a potential n-type conjugated polymer in optoelectronic devices.