Abstract: In order to reduce the concentration of dust in the working face of coal mine and the degree of harm of respiratory dust to the personnel, a wet and dry dust reduction device was developed.Firstly, the spraying experiment was carried out to get the data of effective dust reduction effect.Then, the experimental data were imported to carry out numerical simulation of the spraying process.The effects of the nozzle outward extension distance and spray pressure P_W on the dust trapping net coverage capacity and spray field distribution were determined.The experimental results showed that the optimal nozzle was a 2.4 mm round hole x-type deflector core nozzle.When L_s=25 cm and P_W=7 MPa, the spray field covers the dust traps to the largest extent and achieves effective dust reduction.On-site application and actual measurement were carried out in the return air way of the comprehensive mining mining face of Qipanjing Coal Mine.The results showed that the dust reduction efficiency could reach 90.25%.After the dust reduction, the respiratory dust concentration in the return airway at 20 m, 50 m and 80m from the comprehensive mining face is 0.250 mg/m³,0.203 mg/m³ and 0.179 mg/m³,respectively, which effectively solves the problem of dust pollution in the return airway.