We report an easy method of using SiO2 as the support and HAuCl4 as the precursor for synthesizing a Au/CoOx/SiO2 catalyst that is highly active in low-temperature CO oxidation. The surface of SiO2 was modified with a small amount of highly dispersed CoOx (6 wt%) before the loading of gold. A 78% conversion of CO was achieved at room temperature and 100% at temperatures above 333 K over the Au/CoOx/SiO2 catalyst in CO oxidation. Compared with Au/SiO2, the existence of CoOx greatly enhances the dispersion of gold nanoparticles in Au/CoOx/SiO2, which is responsible for the excellent catalytic performance. (C) 2007 Elsevier Inc. All rights reserved.