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Using ammonium metatungstate, soluble cobalt salt, and organic carbon source as the raw materials, the WC-Co composite powder was fabricated by spray conversion, calcinations and low temperature reduction-carbonization methods. The phase composition, grain size of WC, powder morphology, particle size distribution of precursor powder and composite powder were characterized. Results show that the composite powder was composed of WC and Co phases, The grain size of WC was about 60nm; the appearance of precursor powder was a kind of spherical shell structure, some of them are broken; powder morphology was not changed after calcinations; particle surface produces a large number of pore, the powder morphology was similar with precursor powder, genetic characteristics of morphology was fine; The mean grain size of composite powder was smaller than precursor powder and the particle size distribution was narrow; The mean particle size was increased with the increase of the slurry concentration, liquid feeding rate and with the decrease of centrifugal speed, but the particle size changes slightly with different inlet temperature.