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　TiO　2　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.