Carbon doped TiO2 and pure TiO2 thin films were prepared by atmospheric metal organic chemical vapor deposition (MOCVD) method. Both pure TiO2 and carbon doped TiO2 films are in anatase structure. X-ray photoelectron spectra (XPS) of the carbon doped TiO2 film indicate carbon atoms occupy oxygen sites and form Ti-C bonds in TiO2 lattice. In UV-VIS absorption spectra, it can be found that the carbon doped TiO2 film has a red-shifted absorption edge compared with the pure TiO2 film. In the photocatalytic decomposition experiment of Rh.B, carbon doped TiO2 exhibited remarkably visible light activity.