The photocatalytic TiO_2 thin films in this thesis were prepared by DC reactive magnetron sputtering technique. Photocatalytic activity of them were evaluated by photocatalytic degradation rate of rhodamine B under the radiation of UV. Technological parameters was optimized by orthogonal experiment.Three series films of sputtering pressure,the distance of the substrate-to-target and substrate temperature were prepared . And then they were given analysis about XRD ,AFM, film thickness and photo...