The　preparation　of　high-permselectivity　membranes　is　still　a　challenging　task　due　to　the　limitations　of　conventional　polymeric　membranes.　Herein,　a　chelation-assisted　interfacial　reaction　(CAIR)　was　used　to　construct　an　MOF/polymer　hybrid　layer　on　a　hydrolyzed　polyacrylonitrile　(HPAN)　substrate　to　form　a　ZIF-8/PEI-HPAN　composite　membrane.　Due　to　the　strong　chelating　ability　of　polyethyleneimine　(PEI)　to　metal　ions,　the　formed　ZIF-8/PEI　selective　layer　showed　high　hydrophilicity　and　super　wettability.　Moreover,　its　surface　morphology　changed　from　a　smooth　structure　to　a　ridge-and-valley　structure　via　controlling　the　interfacial　reaction　conditions,　leading　to　enhancement　in　the　permeable　area.　As　a　result,　the　prepared　ZIF-8/PEI-HPAN　composite　membrane　exhibits　a　rejection　of　99.2%　for　Congo　red　aqueous　solution　with　a　permeance　of　up　to　78　L　m(-2)　h(-1)　bar(-1),　which　is　5-8　times　that　of　the　reported　polymeric　membranes　with　excellent　dye　rejection　as　well　as　good　long-term　stability.　We　anticipate　that　the　CAIR　method　can　be　used　as　a　potential　strategy　for　the　preparation　of　polymer-supported　MOF　membranes　with　both　highly　enhanced　permeability　and　good　retention.