Titanium dioxide (TiO2) nanotubes were synthesized via one-step dynamic hydrothermal process from commercial TiO2 powder. The effects of NaOH concentration, reaction time, reaction temperature, stirring process and washing on the morphology, and the exchange ions of the nanotubes were investigated. The morphology of the nanotubes was characterized in detail with transmission electron microscopy and scanning electron microscope. In the dynamic hydrothermal process, stirring can reduce the reaction time of transformation from particles to nanotubes. The nanotubes were formed when the expected reaction temperature reached to 130 A degrees C. Energy dispersive X-ray analysis was used to determine the exchange of sodium ions and protons in washing process. The Na+ ions attached in the nanotubes were removed completely by HCl aqueous solution and deionized water treatments. X-ray diffraction patterns showed the titanate phase of the as-synthesized sample and anatase phase of TiO2 nanotubes after calcination process at 400 A degrees C for 2 h.