The work aims to explore the influencing factors and distribution law of powdery fugitive dust under different filling heights. Based on the gas-solid coupling theory, the interactive effect between particles and air was analyzed during powder filling. The falling powdery fugitive dust was simulated by FLUENT under κ-ε turbulence model and discrete phase model (DPM). The particle concentration, the air speed and the particle tracking proportion were analyzed to confirm the reasonable height of powder filling. Air entrainment was the main factor resulting in fugitive dust, leading to plenty of backflow of particles in the powder bag. Moreover, when the power was 80 mm to 480 mm from the bag mouth, the filling amount of the fugitive dust was the minimum. The fugitive dust can be effectively decreased by changing the height of powder filling in the bag.