Abstract: Ultrafine WC powders were prepared by ball milling and the effects of linear velocities, grinding ball sizes and dispersant on the ball milling process of WC powders with the initial particle size of 1μm were investigated. According to W=P·t, the relationship between particle size and linear speed was obtained when the energy was constant and the most effective linear speed is selected in a certain range of particle size. At the same time, the efficiency of staged grinding was higher than that of grinding at a single line speed, so the same size could be achieved with less cost. In addition, when sodium carboxymethyl cellulose grinding dispersing agent was added, the smaller the particle size was, the more obvious dispersion effect was. when the power output was constant, the time efficiency by adding dispersant was improved by 13% compared with that by adding no dispersant, and the final powder has good dispersion. Finally, the size of the mill ball could determine the particle size. Therefore, the maximum milling efficiency could be achieved by adopting suitable size of the milling ball and milling process according to the target particle size.