Porous　nanoparticles　integrating　the　advantages　of　porosity　and　structural　coherence　typically　possess　numerous　active　sites　confined　on　their　surfaces.　In　this　study,　porous　Co3O4,　Fe2O3　and　Fe3O4　nanoparticles　are　synthesised　by　one-step　pyrolysis　from　metal–organic　frameworks　(MIL-101　(Fe)　and　ZIF-67　(Co))　to　test　the　performance　of　CO　oxidation.　The　prepared　porous　nanoparticles　have　uniform　and　stable　porous　structures　without　obvious　shrinkage　and　structural　collapse.　The　best　catalytic　performance　was　achieved　by　the　porous　Co3O4　nanoparticles,　which　reached　100%　CO　conversion　at　130　1C　without　any　decay　in　catalytic　activity　after　48　h　of　reaction.　DRIFTS　results　present　the　mechanism　of　the　CO　oxidation　by　porous　Co3O4　nanoparticle　catalysis.　The　excellent　catalytic　activity　of　the　porous　Co3O4　nanoparticles　is　related　to　the　large　specific　surface　area　and　surface　oxygen　vacancies.　This　work　provides　a　design　approach　for　synthesizing　other　porous　metal　oxide　nanoparticles　and　has　reference　value　in　the　field　of　CO　oxidation.　This　journal　is　©　The　Royal　Society　of　Chemistry　and　the　Centre　National　de　la　Recherche　Scientifique　2024.