The　artificial　photosynthesis　of　H2O2　from　water　and　oxygen　using　semiconductor　photocatalysts　is　attracting　increasing　levels　of　attention　owing　to　its　green,　environmentally　friendly,　and　energy-saving　characteristics.　Although　covalent　organic　frameworks　(COFs)　are　promising　materials　for　promoting　photocatalytic　H2O2　production　owing　to　their　structural　and　functional　diversity,　they　typically　suffer　from　low　charge-generation　and　-transfer　efficiencies　as　well　as　rapid　charge　recombination,　which　restricts　their　use　as　catalysts　for　photocatalytic　H2O2　production.　Herein,　we　report　a　strategy　for　anchoring　vinyl　moieties　to　a　COF　skeleton　to　facilitate　charge　separation　and　migration,　thereby　promoting　photocatalytic　H2O2　generation.　This　vinyl-group-bearing　COF　photocatalyst　exhibits　a　H2O2-production　rate　of　84.5　μmol　h−1　(per　10　mg),　which　is　ten-times　higher　than　that　of　the　analog　devoid　of　vinyl　functionality　and　superior　to　most　reported　COF　photocatalysts.　Both　experimental　and　theoretical　studies　provide　deep　insight　into　the　origin　of　the　improved　photocatalytic　performance.　These　findings　are　expected　to　facilitate　the　rational　design　and　modification　of　organic　semiconductors　for　use　in　photocatalytic　applications.　©　2024　Wiley-VCH　GmbH.