Abstract: Aiming at the features of ultrafine dust,especially the respirable dust,in the coal mining process,dust-settling and dedusting method used fine water-spray is put forward.The fine mist was produced by rotating spray nozzle,so as to achieve the effect of dust-settling and dedusting.The working principle and dust catching mechanism of fine water mist dust-settling and dedusting were analyzed,and the rotating nozzle for producing fine mist was designed simply.Combined with the features of rotating nozzle,the dust control area is divided into three parts,focused jet zone,control zone and the critical escape zone,which can achieve the ideal effect of dust-settling and dedusting by three-layer control.