During　the　disposal　of　highly　saline　wastewaters,　i.e.,　landfill　leachate　concentrate,　a　conceptual　and　paradigmatic　transformation　from　contaminant　elimination　to　sustainable　resource　extraction　urges　for　novel　selective　membranes.　Mussel-inspired　modification　through　dopamine　self-polymerization　can　be　a　competitive　alternative　to　tailor　the　membrane　surface　properties　for　enhanced　permselectivity　to　target　compounds.　Herein,　co-deposition　of　polydopamine-polyethylenimine　(PEI)　complex　onto　loose　nanofiltration　(NF)　membranes　was　conducted　using　persulfate　as　trigger,　which　resulted　in　a　significant　alteration　in　membrane　surface　properties.　Particularly,　the　pore　size　of　bio-inspired　NF　membranes　decreased,　along　with　a　reduction　in　molecular　weight　cut-off　(MWCO)　from　640　to　298　Da　after　120-min　bio-inspired　coating,　which　yielded　an　enhancement　in　rejection　of　humic　substances　from　95.1%　to　98.9%　in　filtration　of　landfill　leachate　concentrate.　Furthermore,　the　charge　of　membrane　surface　was　tailored　to　be　more　positive　due　to　incorporation　of　positively-charged　PEI,　which　markedly　undermined　the　electrostatic　repulsion　force　for　enhanced　salt　permeation.　These　bio-inspired　NF　membranes　showed　a　superior　selectivity　between　humic　substances　and　salts　for　their　potential　fractionation　from　the　landfill　leachate　concentrate.　Through　an　integrated　NF-based　diafiltration　procedure,　the　concentration　of　humic　substances　was　remarkably　enriched　from　1779.4　to　17247.1　mg·L−1　with　96.0%　recovery.　Additionally,　99.5%　desalination　efficiency　was　achieved,　resulting　in　a　high　purity　(i.e.,　98.3%)　for　humic　substances　as　potential　organic　fertilizer　application.　These　findings　suggest　that　the　bio-inspired　co-deposition　is　an　effective　strategy　to　tailor　the　surface　properties　of　NF　membranes　for　efficient　fractionation　of　humic　substances　and　salts,　in　view　of　sustainable　resource　recovery　from　the　landfill　leachate　concentrate.　©　2020　Elsevier　B.V.