In order to optimize the exhaust ventilation and dust removal system in coal mine tunnels, this paper solves the Reynolds averaged N-S equation and the k-ε turbulence model through numerical simulation, analyzes the dust concentration distribution and wind speed flow field in different working conditions, obtains a set of working conditions with the best dust removal effect, and optimizes the layout of the exhaust duct in the tunnel. The results show that: after optimization, the number of dust particles extracted by the exhaust pipe accounts for 95.95% of the total number of dust particles, and the dust removal effect is significantly improved. This lays a good foundation for dust removal in mine tunnels.