Anatase TiO2 single crystalline nanowires have been successfully synthesized using a simple hydrothermal synthesis method from TiO2 nanoparticles. X-ray diffraction, transmission electron microscopy and high-resolution electron microscopy investigations show the TiO2 nanowires have high crystallinity with diameter range from 30 to 45 nm and length in several micrometers. The TiO2 nanowires can emit blue-green light peaked at 487 nm under excitation at 413 nm. (C) 2002 Published by Elsevier Science B.V.