The　reactive　oxygen　species　(ROS)-mediated　photoinduced　electron　transfer　reversible　addition-fragmentation　chain　transfer　(PET-RAFT)　process　is　an　attractive　tool　to　enhance　the　oxygen　tolerance　of　radical　polymerization　systems.　In　this　paper,　we　investigate　the　relationship　between　the　covalent　organic　framework　(COF)　structure　and　polymerization　performance　based　on　the　O2　center　dot-/H2O　system　by　modulating　the　COF　at　atomic　and　molecular　levels.　We　combine　density　functional　theory　(DFT)　calculations　and　experiments　to　clarify　the　＂oxygen-/water-fueled＂　PET-RAFT　polymerization　mechanism　and　identify　the　key　steps　of　the　protocol.　Based　on　the　modulation　of　the　TD-1　COF　template　structure,　the　relatively　efficient　charge-hole　separation　efficiency　allows　the　matching　of　TD-2　COF　and　TD-3　COF　with　the　O2　center　dot-/H2O　system　to　achieve　high-quality　RAFT　polymerization,　providing　insights　into　the　rational　design　and　development　of　catalytic　systems　with　better　performance.