Metallic and carburized tungsten nanoparticles have been prepared using WCl 6 as precursor. The synthesis steps lead from tungsten hexachloride to tungsten carbide following the sequence WCl 6 → W 0 → α-W 2C → WC. These different compounds have been mainly characterized by X-ray diffraction, TEM observations and adsorption measurements. The total reduction of tungsten hexachloride can be completed at T = 973 K. The carburizing of the metallic lattice into carbide WC is observed at 1223 K although incomplete. At this temperature, crystal growth phenomena appear which are not desired for catalysis applications. The synthesis of nanoparticles supported on activated carbon is accompanied by a decrease of the specific surface area of samples, especially during high temperature carburizing.