Abstract: A series of TiO₂-X films doped with different halides X^－(I^－, Br^－, Cl^－, and F^－) coated on the slide was prepared by dip-coating in the TiO₂ sol into which potassium halide (including KI, KBr, KCl and KF) was introduced. The photo-induced hydrophilicity of TiO₂-I films with different contents I^－ was investigated by testing the change of water contact angle on film’s surface with UV light irradiation time, so was the changes in photoinduced hydrophilicity of TiO₂ films containing different halides. Then, the durability of the TiO₂-X films was investigated by testing the change of water contact angle with dark storage time. Firstly, this result shows that the photo-induced hydrophilic property of TiO₂ films could be enhanced by introducing a little KI into TiO₂ sol, at the best with KI content of 1.0×10^-5 mol•L^-1. However, with the further increase of KI, the photo-induced hydrophilic property of TiO₂-I films would decrease, and even worse than that of pure TiO₂ films when the KI contents is 1.0×10^{-2 mol•L-1. Secondly, introducing KBr and KCl of 1.0×10-5 mol•L-1 into TiO₂ sol could also enhance the photo-induced hydrophilicity of TiO₂ films in an order of KI>KBr>KCl, but introducing KF decreased that of TiO₂ films. Finally, introducing KX (KI and KF) could increase durability of hydrophilicity of TiO₂ films under dark storage condition, and KF shows a better effect than KI. Based on these results, it is suggested that the halides act as electron donors or scavengers to affect the photo-induced hydrophility of TiO₂ films, and the mechanisms of photo-induced hydrophilicity of TiO₂-X films is proposed. However, the higher durability of hydrophilicity of TiO₂-X films compared with pure TiO₂ films may be due to a great stability of hydrophilicity site Ti—OH, which is caused by the strong binding action (hydron bond) between Ti—X and Ti—OH.}