Aiming at the CO treatment problem of sintering gas，the effects of loading，airspeed，NOx，NH3 and repeated temperature rise and fall of precious metal coatings on the activity of self-developed honeycomb CO catalysts are studied. In view of the differences between the sintering gas of each steel mill，a pilot test is carried out under different steel mill conditions. In the pilot study，the catalysts show good stability and are not inactivated by NOx，dust，sintering，and the start and stop of the pilot system. Among them，the 1^# specimen ( loading amount of precious metal coating 210 g /L) runs stably in the flue gas after the double-stage activated carbon desulfurization and denitrification process ( dual-stage AC) in steel mill A for 160 days，and in the flue gas after cyclic fluidized bed desulfurization + SCR denitrification ( CFB + SCR) in steel mill B for 90 days. The 2^# specimen ( loading amount of precious metal coating 180 g /L) runs stably in the flue gas after CFB + SCR in steel mill B for 30 days，and in the flue gas after activated carbon desulfurization + SCR denitrification ( AC + SCR) in steel mill C for 60 days.