Membrane　scaling　is　one　of　the　drawbacks　of　nanofiltration　(NF)　impeding　its　wide　application　in　treatment　of　salt-containing　water.　Especially,　the　high　concentration　of　Ca2+　and　SO(4)(2-)easily　lead　to　a　CaSO4　scale　layer　on　the　membrane　surface,　limiting　the　separation　process.　Herein,　a　zwitterionic　NF　membrane　with　anti-scaling　performance　was　fabricated　through　multi-carboxyl　carboxylate　(sodium　citrate)　incorporated　by　interfacial　polymerization.　Due　to　the　synergistic　effect　of　sodium　citrate,　the　resulting　NF　membrane　had　a　more　negatively　charged　surface　and　a　larger　pore　size　than　the　pristine　membrane.　In　desalination,　this　zwitterionic　NF　membrane　exhibited　a　high　selectivity　(15.9)　between　SO42-　(73.1　+/-　2.4%　rejection)　and　Ca2+　(4.6　+/-　1.4%　rejection)　with　a　flux　of　39.6　LMH,　much　higher　than　that　of　the　commercial　NF　membrane　(NF-270,　a　selectivity　of　1.5).　Based　on　the　high　SO42-　and　Ca2+　selectivity,　it　is　difficult　to　form　a　CaSO4　scale　layer　on　the　membrane　surface,　which　yields　an　excellent　anti-scaling　performance　of　the　resulting　membrane.　Furthermore,　the　zwitterionic　monomer　endowed　the　membrane　with　an　anti-fouling　effect　due　to　zwitterions　materials　have　strong　hydration　to　resist　nonspecific　protein　adsorption.　This　design　strategy　of　ion　selectivity　zwitterionic　membranes　through　the　incorporation　of　carboxylate　provides　guidance　for　the　design　of　highly　ion　selective　anti-scaling　NF　membranes,　which　has　potential　applications　in　water　treatment　for　salt-containing　solutions.