Abstract: “Three-soft” coal seam has the characteristics of unstable roof, easy to caving, soft coal seam, uneven caving of overlying rock in goaf, and easy breakage during mining.In the process of coal mining, the higher the degree of fragmentation of the coal body, the greater the amount of coal dust, and the more serious the pollution to the driving face.In order to study the dust source and control effect of dust in the excavation process of the third mining area, the method of on-site investigation and actual measurement was used to determine the dust source, and the dust production was measured.The research results show that there are four main sources of dust in the excavation process of the third mining areas: coal dust is generated during the cutting and crushing process of the coal mass during the excavation process of the roadheader; During the transportation process, the belt transfer point produces dust; in the case of ventilation, the secondary flying dust produces coal dust.The coal dust in the excavation face is controlled by water spray technology, and the comprehensive dust removal efficiency is 54.26%,66.19% and 20.25%,thus effectively improving the working face environment and protecting the health of workers.