The mechanism of the forming SO2 negative ions and their electrotransfer in the corona discharge electric field was investigated in this paper. The experimental results showed that SO, electrotransfer occurred in the electric field with corona discharge, which had potential applications in removal of SO2 of the flue gas from coal-fired power plants by electrotransfer. SO2 electrotransfer was enhanced by higher electric-field intensity or a larger discharging area. Assistant uniform electric field after the corona discharge electric field would improve SO2 electrotransfer. The increment of the desulphurization efficiency by SO2 electrotransfer might reach as high as 50%. (c) 2006 Elsevier B.V. All rights reserved.