Abstract: In order to clarify the influence of the air outlet width and the ratio of radial and axial air outlet of the wall attached air duct on the dust control effect of the fully mechanized face, taking a fully mechanized face in Fengjiata Coal Mine as the prototype, the numerical simulation of the long pressure and short extraction ventilation roadway model is carried out by using FLUENT software, and the simulation results are verified on the spot. The results show that when the pressure extraction ratio is kept at 1.3 and the length of the radial air outlet is 0.8 m, with the increase of the width of the air outlet, the dust concentration in the roadway space first decreases and then increases, and the width of the air outlet is changed. When the width of the air outlet is 0.05 m, the dust concentration at the driver is reduced to 100 mg/m³, 20 m away from the heading face, there is basically no dust in the roadway, and the dust control effect is the best. Keeping the optimal outlet width of 0.05 m. As the radial and axial air outlet ratio decreases, the dust concentration in the roadway first decreases and then increases, when the radial and axial air outlet ratio is 1∶2, the dust is centrally controlled in the negative pressure suction area, and the dust concentration at the driver’s position of the anchor digger decreases to 1.2 mg/m³. At this time, the radial outlet wall attached air duct has the best dust control effect.