A simple method based on sol–gel method was developed to prepare vanadium ions doped TiO 2 nanocrystalline at low temperature. Thus-obtained vanadium doped TiO 2 was proved to be V x Ti 1− x O 2 solid solution. Doping vanadium could enhance the formation of stable phase. Its optical absorption spectrum shows a red shift to 445nm. Photodegradation experiments suggest that thus-prepared vanadium doped TiO 2 nanocrystalline can be excited by visible light and is a good photocatalyst under daylight. These properties are the same as the vanadium doped TiO 2 prepared under high temperature conditions (⩾350°C). However, in the present work, the vanadium doped TiO 2 crystal particle is very uniform and fine, about 5nm. It is much smaller than the production prepared under high temperature.