By employing carbon dioxide as one source of reaction gases, carbon-doped Ti–O films were fabricated via reactive magnetron sputtering deposition. The chemical bonding configurations and microstructure of the films were analyzed by Raman spectrum and SEM, respectively. The effect of pH on the photocatalytic activities of the films was determined via evaluation of the decolorization rate of methyl orange under alkali, acid and neutrality conditions using UV light irradiation. Electrochemical impedance spectroscopy and potentiodynamic polarization tests were employed to determine the anti-corrosion properties. Compared with the C-free Ti–O film, the C-doped Ti–O films exhibit superior corrosion resistance. Furthermore, the results of the photodegradation experiment suggest that the C-doped Ti–O films have excellent photocatalytic activities and, for methyl orange, those with higher carbon content exhibit hyper-photodegradative effect under the alkali condition.