Kinetic　factors　frequently　emerge　as　the　primary　constraints　in　photocatalysis,　exerting　a　critical　influence　on　the　efficacy　of　polymeric　photocatalysts.　The　diverse　conjugation　systems　within　covalent　organic　frameworks　(COFs)　can　significantly　impact　photon　absorption,　energy　level　structures,　charge　separation　and　migration　kinetics.　Consequently,　these　limitations　often　manifest　as　unsatisfactory　kinetic　behavior,　which　adversely　affects　the　photocatalytic　activity　of　COFs.　To　address　these　challenges,　we　propose　a　methoxy　(−OMe)　molecular　engineering　strategy　designed　to　enhance　charge　carrier　kinetics　and　mitigate　mass　transfer　resistance.　Through　strategic　modulation　of　the　position　and　quantity　of　−OMe　units,　we　can　effectively　manipulate　the　p-π　conjugation,　thereby　enhancing　charge　separation　and　migration.　Moreover,　COFs　enriched　with　−OMe　moieties　exhibit　enhanced　mass　transfer　dynamics　due　to　the　hydrophilic　nature　of　methoxy　groups,　which　facilitate　the　diffusion　of　reactants　and　products　within　the　porous　structure.　This　approach　is　hypothesized　to　drive　an　efficient　photocatalytic　hydrogen　evolution　reaction.　©　2024　Wiley-VCH　GmbH.