K2S2O8 and KMnO4 solutions were used as oxidation absorption solutions. The original carrier gas N2 was mixed with HCl gas in different proportions. The effects of HCl concentration and reaction temperature on mercury removal efficiency of each system were analyzed. The results show that the KMnO4 system has good adaptability to HCl and high oxidation absorption efficiency, which can be used as oxidation absorption reagent for mercury removal. The K2S2O8/Fe2+ system has a high oxidation absorption efficiency. However, when the HCl concentration increases to more than 80 mg/m3, the oxidation absorption efficiency shows a downward trend. When the reaction temperature is 20~ 80 ℃, the mercury removal efficiency of KMnO4 system is relatively stable, and HCl has a positive effect on the oxidation absorption system. As the reaction temperature increases, the mercury removal efficiency of the K2S2O8/Fe2+ system increases first and then decreases. The highest mercury removal efficiency is 99.76% at 40 ℃.