A series of mesoporous CuO-Fe2O3 composite oxide catalysts with different CuO contents were prepared by a surfactant-assisted method of nanoparticle assembly. The prepared composite oxides were characterized by X-ray diffraction, N-2 adsorption, transmission electron microscopy, hydrogen temperature-programmed reduction, thermogravimetry-differential thermal analysis and X-ray photoelectron spectroscopy. Their catalytic behavior for low-temperature CO oxidation was studied by using a microreactor-GC system. These mesoporous CuO-Fe2O3 catalysts possess a wormhole-like mesostructure with a narrow pore size distribution and high surface area, exhibiting high catalytic activity and stability for low-temperature CO oxidation. The catalytic behavior depended on the CuO content, the precalcination temperature, the surface area and the particle size of the catalysts. The catalyst with 15 mol% CuO content and calcined at 300 degrees C exhibited the highest catalytic activity and stability. (C) 2007 Elsevier B.V. All rights reserved.