Abstract: The spray characteristics have an important impact on the dust reduction effect of spray, and improving the atomization effect can effectively improve the working face environment. The interaction between the internal and external flow fields of the pressure nozzle and the liquid medium is complex. There are some problems in the current spray research, such as no clear basis for the selection of on-site application nozzles, blindness in the control of spray characteristics, etc., which bring difficulties to the efficient dust suppression of the working face. Taking all kinds of single nozzles commonly used in the mine as the research object, this study studies the influence of three key parameters of nozzle type, water supply pressure and aperture on the four spray characteristics of range, flow, atomization angle and axial jet velocity, studies the importance of different parameters on the influence of spray characteristics by using the grey correlation analysis method, and optimizes the nozzles at different positions of the underground shearer and hydraulic support according to the analysis results, and the spray process of different types of nozzles was optimized. The results show that the type of single nozzle, water supply pressure and aperture have different influence forms and importance on macro spray characteristics; SMP nozzle and spiral nozzle are respectively suitable for internal and external spray of shearer, swirl core nozzle is suitable for front probe beam and tail beam nozzle, fan nozzle and hollow cone nozzle are respectively suitable for roof beam and inter rack spray; the importance of the influencing factors is used to determine the sensitivity index of the atomizing nozzle, optimize the spray control of the dust suppression system, and effectively improve the matching degree between the nozzle and the engineering environment. The research results can provide a theoretical basis for accelerating the construction of a highly sensitive, multi-directional, fully covered and controllable wet dust removal system in coal mines.