Au-buffered TiO2 thin films have been prepared by radio frequency magnetron sputtering method. The structural and morphological properties of the thin films were characterized by X-ray diffraction, scanning electron microscopy, and atomic force microscopy. The photocatalytic activity of the samples was evaluated by the photodecomposition of methylene blue. The Au-buffer thin layer placed between the TiO2 thin films significantly enhanced photocatalytic activity by 50%. Annealing the Au-buffered TiO2 thin film at 600 degrees C decreased the film roughness, but it increased the surface area and anatase crystalline size, enhancing the photocatalytic activity. (C) 2008 Elsevier B.V. All rights reserved.