A new wet flue gas desulfurization method by reaction across the falling liquid film on the outside surface of axial finned-tube bundle and its principles of removal of SO 2 are presented in this paper.The effects of different styles of tube bundle,and the pitch of tubes,flue gas velocity,gas-liquid ratio and flue gas temperature on desulphurization efficiency and the moisture content of flue gas are studied.The experiment results show that desulphurization effect is better for flue gas at 65 ℃,4.0 m·s -1against the tube bundle of 10 rows with relative pitch of staggered rows S 1/d=2.1,S 2/d=1.8.