Au/titanium dioxide nanotubes (Au/TiO2-NTs) catalysts are prepared by a simple method using galvanic deposition of gold nanoparticles on TiO2-NTs as support. TiO2-NTs are fabricated by anodizing titanium foil in a dimethyl sulfoxide (DMSO) fluoride-containing electrolyte. Scanning electron microscope and energy-dispersive X-ray spectroscopy results indicate that nanotubular TiO2 layers consist of individual tubes of about 50-80 nm diameters and gold nanoparticles with a size range of 30-40 nm are well-dispersed on the surface of TiO2-NTs support. The electro-catalytic properties of Au/TiO2-NTs catalysts toward electro-catalytic oxidation of hydrazine are investigated by cyclic voltammetry. Compared to flat gold electrodes. Au/TiO2-NTs catalyst shows much higher electrochemical activity. This may be attributed to the uniform dispersion of gold nanoparticles on TiO2-NTs, smaller particle size and unique properties of TiO2-NTs support. In addition, the mechanism of hydrazine electrochemical oxidation catalyzed by Au/TiO2-NTs is investigated. (C) 2010 Elsevier B.V. All rights reserved.