Abstract: The research status of CO selective catalytic reduction (CO-SCR) catalysts under oxygen conditions in recent years was introduced. The research progress of Ir-based, Pd-based, Cu-based and Co-based catalysts was mainly introduced. The influence of type of carrier, doping modification and active component on the catalyst activity was analyzed. The effects of H₂O and SO₂ on the activity of catalysts were investigated, and the reaction mechanism of CO-SCR was investigated to provide reference for improving the active of CO-SCR catalysts under oxygen condition. Finally, it is pointed out that it is the possible research directions of CO-SCR in the reaction mechanism of O₂ and the toxic mechanism of SO₂ and H₂O on the catalyst under oxygen condition in the future.