TiO2-polyaniline (PANI) composites were prepared by thermal oxidation of titanium substrate combined with chemical polymerization of aniline. Their chemical structures were determined by infrared (IR) spectroscopy and x-ray analysis. Their morphological structures were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Their electro- and photoelectrochmical properties were examined by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) analysis. The results showed that their photoelectrochemical behavior was better than that of TiO2 electrode; among them the more PANI existed in composite the higher was the anodic photoelectrochemical current. It was also found that the composite has structure in the range of nanosize.