Abstract: In order to find out air and respirable dust distribution laws of fully mechanized mining face with large mining height, based on standard k-ε turbulence and disperse phase models, a geometric model of fully mechanized mining face with 8 m mining height is built by gambit software. Air velocity and respirable dust concentration distribution were simulated at 1.2 m/s of inlet air velocity by fluent software. The results showed that a high air velocity area beyond 2 m/s was formed among 2 to 3 m above the shearer, which appeared horizontal migration downwind the shearer. And the high wind speed area is about 30 m longer than that of downwind coal cutting. A high respirable dust concentration area beyond 250 mg/m³ was formed among 1 to 2 m above the shearer. The respirable dust concentration at the height of 3 to 5 m was high in sidewalk due to horizontal diffusion of dust, and the affected area was larger when cutting coal downwind. In the downwind of the shearer, respirable dust concentration at the height of breathing zone declined from coal wall to sidewalk, which caused more pollution to sidewalk when cutting coal downwind. And the respirable dust generated from moving support mainly migrated around the roof, which was hard to settle.