In order to reduce the large right-angle bend wind well local resistance in some iron ore, fluent software based on 2 d plane and standard turbulence model and SIMPLE arithmetic was adopted, which respectively simulated the four different modification angle （90 °, 45 °, 60 °, 30 °） under the condition of the flow of the wind, the results showed that the entrance 30 ° combining export  60 ° could decrease the bend loss of energy. The construction was made based on the method and wind test was conducted after the improved system, the local resistance reduced by 230.94 Pa, mine total air volume increased by 47.57 m3/s, which improved the ventilation of mine, finally that the lower resistance could bring the economic benefits of mine production was analyzed.