To improve optical property and coloration effect, La, Nd and Bi co-doped TiO₂ films were synthesized via a Sol-Gel method, by using butyl titanate as precursor on the surface of ITO glass substrate. Structural surface morphologies and electrochromic properties of the as-prepared films were examined with TG-DTA、XRD、UV-vis and Electrochemical workstation. The results showed that anatase TiO₂ formed from TiO₂ dry gels after heat treatment at 400℃, 500℃, 600℃, and showing tendency of the higher the temperature heat treatment, the more complete the crystal development. La, Nd and Bi doped TiO₂ increased the disorder of the TiO₂ octahedron, resulting in increase of the amorphized degree. TiO₂ films prepared with acurate 12% tetrabutyl titanate exhibited the best electrochemic properties. TiO₂ films heat-treated at 500℃ showed excellent electrochemical properties. TiO₂ films separately doped with molar amount fraction of 8%La, 18%Nd, 6%Bi, possess excellent electrochemic properties,and single doping effect is in the order of 6% Bi < 8 %La<18% Nd. La-Nd-Bi co-doped TiO₂ is anatase with a very high amorphized degree, with the best cyclic valtammentry and highest amorphized degree when the molar amount ratio of La:Nd:Bi=4^:10^:2.