Tungsten oxide (WO3) nanomaterials have been extensively researched for applications such as semiconductor gas sensors and photocatalysis. We have synthesized WO3 nanorods (diameters: 100-150 nm; lengths: 400-500 nm) with high yields by thermal chemical vapor deposition (CVD). In our unique two-step heating process, catalysts were not required in the temperature zone (500-600 degrees C) of substrate. It suggests the experimental conditions played a dominant role in the growth of WO3 nanorods, especially in the case of the O-2 flow rate and substrate temperature. Moreover, this relatively simple growth process can lead to effective large-scale production of WO3 nanorods. (C) 2011 The Electrochemical Society. [DOI: 10.1149/1.3586784] All rights reserved.