Abstract: In view of problems such as excessive dust concentration in working face and deterioration of working environment in mines caused by wide application of mechanized mining. We put forward technical means to optimize technical parameters of water injection and dust control in coal seam so as to increase water content of coal seam to be exploited. Using the simulation software COMSOL, the relationship between the process parameters such as water injection pressure and time and the infiltration effect of coal seam was studied. The third-order polynomial fitting function curve of wetting radius and water injection time under the condition of medium pressure water injection is obtained. The research results show that the infiltration effect of coal seam with medium pressure water injection is better. When the water injection pressure is 5 MPa, the optimal water injection duration is 5 h.