Removal　of　natural　organic　matter　(NOM)　from　drinking　water　by　membrane　technology　is　attracting　increasing　attention.　However,　the　fouling　of　the　membrane　by　NOM　is　one　of　the　biggest　obstacles　restricting　its　widespread　application.　Therefore　an　anti-NOM　fouling　polyelectrolyte　complex　(PEC)　membrane　was　obtained　by　creating　a　negatively　charged　multilayer　on　a　polyacrylonitrile　(PAN)　supporting　membrane　using　a　layer-by-layer　assembly　method.　To　improve　the　stability　of　the　PEC　membrane,　the　electrostatically　assembled　(poly(ethyleneimine)/poly(sodium　4-styrenesulfonate))　n/PAN　membranes　were　crosslinked　by　glutaraldehyde.　It　was　found　that　the　zeta　potential　of　the　membrane　surface　decreased　after　chemical　crosslinking,　which　further　improved　the　electrostatic　repulsion　to　NOM　and　thus　improved　the　anti-NOM　fouling　property.　Results　of　a　30　day　nanofiltration　operation　showed　the　crosslinked　membrane　had　good　stability　and　gave　a　higher　rejection　of　NOM;　the　permeance　of　the　crosslinked　membrane　was　double　that　of　the　uncrosslinked　membrane.