An nanoparticles with a diameter of several nanometers (nm) attached onto metal oxides are considered as excellent catalytic materials. In this work, an individual SnO2 nanobelt is decorated by Au nanoparticles with a scale below 5 nm by means of conventional thermal evaporation. This novel Au/SnO2 complex nanostructure is configured to detect the occurrences of CO oxidations at low temperature region (< 250 degrees C). Electrical property measurement is used to detect the captures and releases of oxygen species on the surface of SnO2 nanobelt, reflecting the occurrences of CO oxidations. As compared with the same SnO2 nanobelt without the architectures of Au nanoparticles, the enhanced CO oxidations on the surface of Au/SnO2 nanostructure are attributed to catalytic reactions improved by Au nanoparticles with small size and the introduction of Au/SnO2 interfaces. (C) 2007 Elsevier B.V. All rights reserved.