Separated and open end TiO2 nanotubes were successfully fabricated through a two-step chemical etching process. The separation of the close-packed TiO2 nanotube arrays can be attributed to the infiltration and chemical etching of the 0.15 wt% HF water solution along the gaps of the nanotubes. The end-opening of the tubes can be attributed to the chemical etching of the HF vapors, as well as the surface imperfection and residual stress present at the ends of the nanotubes. Considering that the size of the open tubes can be adjusted, well defined nanotubular arrays can be created not only for dye-sensitized solar cells but also for pollution removal and biomedical applications.