The effect of Ce-doping on microstructure of TiO

2

nanoparticles is reported in this paper. The Ce-doped TiO

2

samples were prepared by the sol-gel method under acidic condition and calcined at different temperatures. Influence of the cerium dose and calcination temperature on the microstructure of the TiO

2

nanoparticles was studied by X-ray diffraction （XRD）

small angle X-ray scattering（SAXS） and X-ray absorption fine structure techniques. It is found that the cerium doping inhibits the growth of nanoparticles and the transformation of anatase to rutile at elevated temperature. The "self-similar" fractal structures are dependent on the Ce content and annealing temperature. The core-shell model was used to describe the near-neighbour structural parameters around Ti.