The spherical tungsten powder was fabricated by spray-drying method combined with hydrogen reduction using ammonium metatungstate (AMT) as raw materials. The powder morphology, mean particle size, particle size distribution and phase transformation process of reduction were characterized by SEM, TEM, XRD and laser diffraction particle size analyzer, respectively. Results show that the morphology of the powder prepared by spray drying is hollow sphere, and both of AMT and WO3 powder has similar good spherical structure with smooth surface. TEM results indicate that the process parameters, such as the slurry concentration, compressed air flow rate, and liquid feeding rate, play important roles in controlling the performance of AMT microspheres, such as the size distribution. It is found that calcination has no effect on the particle morphology and phase composition. The mean size is increased with the increase of the slurry concentration and compressed air flow rate, but the size distribution changes slightly with different liquid feed rates. The X-ray diffraction patterns indicate that α-W phase is obtained after reduction at 550 oC for 2 h in hydrogen atmosphere, but WO3 still exists; after reduction at 750 oC for 2 h, WO3 disappears, and α-W phase exists in the powder