In recovery system of seawater flue gas desulfurization (SWFGD) process, a novel integrated electrochemical-aerating oxidation method is developed. The influences of process factors such as anode-cathode brush assembly, applied current and dilution ratio on S(IV) oxidation performance are investigated, in connection with S(IV) oxidation rate, the anodic potential range of S(IV) oxidation, energy consumption and total amount of seawater. Compared with the conventional aerating process, the integrated oxidation is confirmed as an energy-efficient and seawater-saving improvement for existing SWFGD recovery system. Based on these experiment results, the reaction mechanism is also proposed. The electrochemical reactions on modified polyacrylonitrile-based carbon fiber (MPAN-CF) brush anode and polyacrylonitrile-based carbon fiber (PAN-CF) brush cathode, together with aerating process, synergistically accelerate the S(IV) oxidation. Therefore, integrated electrochemical-aerating oxidation method using MPAN-CF&PAN-CF anode–cathode brushes is promising for industrial application and is expected for the treatment of high sulfur flue gas in future.