Atomization process of liquid and breakup process of liquid ejected from the nozzle were described and analyzed in this paper. At the same time, working principles of atomizing dust suppression system of vertical shaft roadheader were researched, as well as introducing dust reduction efficiency under different dust removal mechanisms to find out its influencing factors. The influences of nozzle layout, the number of nozzles, the diameter of nozzle outlet, the angle of atomizing, the length of spray zone, the pressure of spray, the diameter of fog, the velocity of fog and the concentration of fog on the efficiency of spray dust were analyzed, which provided theoretical basis for similarity optimization design of atomizing dust suppression system.