Anatase Fe-doped TiO2 nanoparticles with 10-15nm particles sizes were directly prepared with amorphous TiO2 nanoparticles and Fe(NO3)(3)center dot 9H(2)O by hydrothermal method. The TiO2 crystallite grain sizes decreased with the increase of Fe contents. When Fe contents increased, the diffuse reflectance spectra of Fe-doped TiO2 nanoparticles displayed a red shift in the band gap transition. And the absorbing band edge moved to visible range when the Fe contents were more than 2 mol%. XPS analysis showed that Fe3+ was not on the surface of TiO2 nanoparticles, but inserting into the matrix interior. As a result, the photoactivity degradation of MB on Fe-doped TiO2 nanoparticles decreased. (C) 2007 Elsevier B.V. All rights reserved.