In　this　work,　we　presented　a　facile　and　novel　strategy,　chelation-assisted　in　situ　self-assembly,　to　prepare　the　loose　polyacrylonitrile　(PAN)-based　nanocomposite　membrane　for　dye　desalination.　Based　on　the　chelate　reaction　polyethyleneimine　(PEI)　with　metal　ions,　an　Ag+-PEI　complex　layer　was　deposited　onto　the　hydrolyzed　PAN　surface.　Then,　the　chelate　complex　layer　was　served　as　the　templates　to　in-situ　synthesize　the　vitamin　E　succinate　(VES)-functionalized　AgCl　nanoparticles　,　which　were　uniformly　distributed　on　the　membrane　surface　and　provided　additional　transport　pathways　for　water　molecules.　The　prepared　nanocomposite　membrane　achieved　the　permeability　of　106.4,　101.2　and　92.3　L　M-2　h(-1)　MPa-1,　which　was　20-50%　higher　in　comparison　with　that　of　the　pure　Ag+　-PEI@HPAN　membrane,　with　corresponding　rejections　of　99.2%,　99.5%　and　99.8%　to　crystal　violet,　acid　fuchsin　and　congo　red　solution　at　the　concentration　of　0.1　g　L-1.　Meanwhile,　this　membrane　possessed　a　low　inorganic　salts　rejection　(6.2%,　9.6%　8.3%　and　12.8%　for　MgCl2,　NaCl,　MgCl2　and　Na2SO4)　and　good　stability　during　the　60　h　filtration　of　dye-salt　mixture.　We　anticipate　that　this　novel　route　could　be　applied　to　prepare　the　polymer-supported　nanocomposite　membrane　with　enhanced　separation　performance.