This paper introduces the principle of dust reduction of coal seam water injection, and takes Xinqiao Coal Mine as an example to analyze. The dust production of No.22 coal seam in Xinqiao Coal Mine is large. Through the experimental analysis of coal samples in No.2106 Face and No.2501 Face, according to MT / T1023-2006 standard, it is determined that the coal seam has water injection conditions. The original coal sample, coal sample soaked in water and coal sample added with wetting agent were tested for dust production ability by drop hammer method. The results show that clean water and wetting agent treatment can effectively reduce the dust production of coal samples. Combined with the analysis of coal seam water injection and dust production capacity, this paper proposes a set of comprehensive dust prevention measures for Xinqiao Coal Mine. It is recommended to increase the water injection pressure at the 2106 working face, add active ingredients at the 2501 working face, and add wetting agents during the water injection process to enhance the dust reduction effect and ensure the safety of mine production and the health of workers.