We have synthesized anodic titanium oxide nanotubes with a high aspect ratio by anodizing a metallic titanium sheet in a perchloric acid based electrolyte, and fabricated a dye-sensitized solar cell (DSSC) by using the nanotubes as its negative electrode. Rapid and homogeneous anodization has been accomplished using a mixture of perchloric acid and ethanol as the electrolyte. Furthermore, it was demonstrated that the diameter of anodic titanium oxide nanotubes could be varied by adjusting the anodization conditions, such as the electrolyte and the anodic potential. The measured characteristic of the DSSC showed that anodic titanium oxide nanotubes have a potential for improving the performance of a DSSC. (c) 2007 The Electrochemical Society.