Abstract: The distribution of flow field in the tower of wet flue gas desulfurization affects the desulfurization efficiency directly． A kind of desulfurization reaction method adding swirl atomizing layer in the spray tower was put forward． Based on Fluent software plant form，this paper studied 3D numerical simulation and analysed the flue gas flow features of different conditions in the desulfurization tower， reconstructed and optimized the flue gas flow field by changing the parameters of the spray nozzles such as arrangement angle，amounts as well as flue gas spray velocity． The research results indicated that，if the diameters rate d /D of the swirl atomizing layer was about 0. 6 and the amount of the nuzzles was more than eight，the stable helical field could be formed． In addition，slurry discharged from the nozzle at the rate of 15 ～ 20 m/s was beneficial for the flue gas to be the optimum desulfurization speed range． The result provided reference on the reconstruction of flue gas desulfurization tower for large-capacity boilers．