Au-CeO2/SiO2 catalysts were synthesized by Adsorbed-Layer Reactor Technique and characterized by TEM, XRD and Raman spectroscopy. It was found the pre-addition of NaOH changed the hydrolysis of HAuCl4 in adsorbed layer and then regulated the morphology and microstructure of Au and CeO2. In the catalysis of benzene oxidation, with the increase of pre-addition amount of NaOH, the high-temperature activity increased monotonously, which was consistent with the change of crystallite size of Au. However, the low-temperature activity presented a maximum with increase of pre-addition amount of NaOH, which was verified being agreement with the change of red-shift of F-2g peak of CeO2. The results showed that the high-temperature activity depended on Au size and the low-temperature activity was affected by CeO2 microstructure. The experiment of metal ion doping offered another proof. (C) 2013 Elsevier B.V. All rights reserved.