Carbon　monoxide　is　widely　present　in　coal-fired　flue　gas　and　automobile　exhaust.　The　catalytic　reduction　of　NO　by　incompletely-burned　CO　can　simultaneously　remove　NO　and　CO.　The　catalyst　plays　a　decisive　role　in　the　process.　In　this　paper,　the　recent　research　results　of　CO　catalytic　reduction　of　NO　under　oxygen　are　reviewed　systematically.　The　catalyst　preparation　method,　doping　modification　and　reaction　conditions　of　Pd　based,　Ir　based,　Cu　based,　other　precious　metals　and　metal　oxide　catalysts　are　analyzed.　The　effects　of　O2　concentration,　H2O　and　SO2　on　the　catalytic　reaction　are　also　investigated.　The　active　sites　and　catalytic　mechanism　of　different　catalysts　are　summarized　and　compared.　The　inhibition　mechanism　of　O2　in　the　catalytic　reduction　process　was　proposed,　and　the　catalytic　activity　sequence　of　these　kinds　of　catalysts　was　obtained.　Finally,　the　research　directions　of　further　study　are　given　as　the　inhibition　mechanism　of　O2,　reducing　the　use　of　precious　metals,　and　adding　active　additives.　©　2018,　Chemical　Industry　Press.　All　right　reserved.