Abstract: The exhaust air pollution could cause the cross infection between livestock buildings, and affect air quality outside the farm. This paper designs a biomass dust break wall to reduce the exhaust pollution. The field experiment results show that TSP concentration reduced by 77%, PM10 reduced by 55%, total microbes and colibacillus concentration reduced by more than 85%. Odor level in the area downwind of the biomass dust break wall is only half of that in upwind. Using the biomass dust break wall system, the heavy polluted exhaust air from livestock buildings can be cleaned to normal level in resident area.