Abstract: Titanium dioxide (TiO2) films with different crystalline structures were prepared via solgel dip coating method. The influences of humidity, substrate and catalyst acid on the film quality such as integrality and crystallization were investigated. Pure anatasetyped and rutiletyped TiO2 films with homogeneous and compact nanostructure were prepared under the optimized conditions. The surface characters of both types of TiO2 films were studied by surface energy test and infrared spectrum analysis. The results showed that bothtyped films are able to capture OH radicle, but anatasetyped TiO2 film shows a stronger capability, which leads to a higher surface energy and better hydrophilicity.