Ceria nanoparticles were synthesized by two  different wet soft chemistry routes, the thermal decomposition of a tartrate-based precursor and the reverse microemulsion method. The tartrate-based precursor was characterized by FTIR spectroscopy and thermal analysis, whereas the sample isolated from the microemulsion by X-ray diffraction. The precursors were calcined at 500°C, 3h in air and oxide nanopowders were investigated by X-ray diffraction, transmission electron microscopy and selected area electron diffraction. Ceria sample obtained by decomposition of tartrate-based precursor has nanoparticles in the range of 6 - 12 nm with a slight tendency of agglomeration and a specific surface area of 28 m²/g, whereas the sample synthesized by reverse microemulsion method has nanoparticles of 6 nm average size, with very narrow size distribution, and higher specific surface aria, 68 m²/g.