By the sol-gel method, the polyethylene glycol (PEG2000) doped TiO2 films are prepared. The effects of additive amount of PEG2000 on the microstructure, surface morphologies, transmissivity, and self-cleaning properties of TiO2 films are investigated. With the ultraviolet lights as light sources, the effects of PEG2000 concentrations on the photocatalytic activity of TiO2 films are analyzed. The results show that all the structures of the prepared films are anatase; the microstructure of TiO2 films can be regulated and controlled by the regulation of the additive amount of PEG2000 and thus their optical and self-cleaning properties are controlled.