With the industrial development,the use of material superfines has beenwidened.The best way to produce the superfines is by air-flow crushing.The particlescrushed by air flow have advantages over the mechanically grinded product in fineness,pu-rity and evenness etc,Meanwhile,some materials with special physical properties such aslow melting point and high hardness etc can be crushed by high-speed air flow rather thanmechanical process.Referring to his our practice the anther described the working princi-ple fo air-flow crushing and the control of particla sixa and air-flow velocity;pointed outthat the key to the acquisition of better crushing result lies in the control of forces appliedon the particles,the reasonable design of nozzle and the adjustment of jet angle.