The electrochemical and electrooptical properties of an ionic conjugated polymer, poly[2-ethynyl-N-(p-cyanophenylazophenyl)oxyhexylpyridinium bromide] (PCEPB) were studied. The cyclovoltamograms of this polymer exhibited the irreversible electrochemical behaviors between the doping and undoping peaks. The oxidation current density of PEPB versus the scan rate is approximately linear relationship in the range of 30mV/sec similar to 120mV/sec. The exponent of scan rate, x value of PEPB, is found to be 0.6. The absorption spectrum starts around 800nm and shows a strong absorption band at visible region due to the pi ->pi(*)interband transition of the polymer backbone, which is a characteristic peak of the conjugated polyene backbone system. The photoluminescence spectrum showed that the PL peak is located at 542nm corresponding to the photon energy of 2.29 eV.