Electrochemically anodized TiO2 nanotube (NT) arrays on Ti foils have been in great interests recently attributing to the wide applications. The net growth rate of TiO2 NT array is determined by electrochemical etching of Ti foil and chemical dissolution of the formed TiO2 NTs. While the TiO2 NT growth becomes a diffusion controlled process after certain growth time. Here, we report the influence of ultrasound on the growth process of TiO2 NT arrays.The results indicate that ultrasound can significantly alter the relative rates of these reactions and adjust the geometries of the TiO2 NT arrays. (C) 2009 Elsevier Ltd. All rights reserved.