Covalent　organic　frameworks　(COFs)　are　a　class　of　promising　photocatalysts　for　conversing　light　energy　into　chemical　energy.　Based　on　the　tunable　building　blocks,　COFs　can　be　well-designed　as　photocatalyst　for　mediating　reversible　addition-fragmentation　chain-transfer　(RAFT)　polymerization.　Herein,　1,3,6,8-tetrakis(4-formylphenyl)pyrene　(TFPPy)　and　2,2″-bipyridine-5,5″-diamine　(Bpy)　are　chosen　to　construct　imine-based　TFPPy-Bpy-COFs　for　catalyzing　RAFT　polymerization　of　methacrylates　under　white　light　irradiation.　The　well-defined　polymers　with　precise　molecular　weight　and　narrow　molecular　weight　distribution　are　obtained.　The　switch　on/off　light　experiments　suggest　excellent　temporal　control　toward　RAFT　polymerization　system　and　the　chain-extension　reaction　indicates　high　chain-end　fidelity　of　macro-initiators.　Mechanism　study　clarifies　that　the　electron　transfer　between　excited　state　of　TFPPy-Bpy-COFs　and　RAFT　agent　can　form　living　radicals　to　mediate　polymerization.　This　methodology　provides　a　novel　platform　for　reversible-deactivation　radical　polymerization　using　COFs　as　heterogeneous　catalysts.　©　2021　Wiley-VCH　GmbH