We have prepared the novel gallium oxide (Ga2O3) nanomaterials on SiO2 substrates by a thermal evaporation of GaN powders. We found that the products consisted of the nanobelts with additional nanostructures formed on the sides of nanobelts. The nanobelts had a single-crystal line monoclinic structure with a width in the range of 100-300 nm. We have discussed the possible mechanism leading to the formation of the Ga2O3 nanomaterials. Photoluminescence spectrum under excitation at 325 nm showed a blue emission. (C) 2004 Elsevier B.V. All rights reserved.