In order to solve the problem of coal dust pollution in the Xinzhi Mine, the 2-216 mining face was taken as the study object, based on the analysis of geology of the mining face, the gas storage situation and the application of drilling water injection to eliminate dust, to verify the reasonableness of free water on the mining face dust reduction, in combination with the application of water injection and dust suppression, the optimum water injection pressure helped to increase the water content in the seam with increasing water injection time and water injection. On this basis, the concentration and content of coal dust can be reduced at the mining face and the air return roadway.