ZnO nanorods are prepared by a hydrothermal process with cetyltrimethylammonium bromide ( CTAB) and zinc powder at 182 degrees C. The samples are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The gas sensing properties of the materials have been investigated. The results indicate that the as-prepared ZnO nanorods are uniform with diameters of 40 - 80 nm and lengths about 1 mu m, the relatively high sensitivity and stability of these sensors made from ZnO nanorods demonstrate the potential for developing a new class of stable and very sensitive sensors. (C) 2005 Springer Science + Business Media, Inc.