Nitrogen-doped titanium oxide photocatalysts, which were reported to be activated by visible light irradiation as well as ultraviolet irradiation, have been prepared by pulsed laser deposition method using Ti, TiO, TiO2 and TiN targets in nitrogen/oxygen gas mixture. As a result, it is found that film properties such as color, crystalline structure and atomic composition rate strongly depend on the target material and nitrogen concentration ratio in the gas mixture. It is also suggested that these films under UV light irradiation exhibit almost the same decomposition ability of methylene blue. However, the photocatalytic activity of the nitrogen-doped TiO2 film prepared using TiN target is higher than that of the other films prepared by Ti, TiO and TiO2 targets under normal fluorescent light irradiation. (C) 2004 Published by Elsevier B.V.