Today,　the　steroid　estrogens　(SEs)　discharged　with　non-point　source　pollutions　have　brought　potential　risks　to　the　environment.　It　is　necessary　to　develop　new　restoration　strategies　for　SEs.　In　this　study,　a　heterogeneous　nano-zero-valent　iron　Fenton　system　loaded　with　citrate　ligands　(C-nZVI)　was　proposed.　It　obviously　enhanced　the　degradation　rates　of　17β-estradiol　(17β-E2),　and　the　degradation　efficiency　under　neutral　condition　was　also　enhanced　by　4.59　times.　The　characterization　of　C-nZVI　showed　that　citrates　and　their　hydroxyl-rich　fragments　formed　a　spatial　network　structure　and　covered　on　its　surface.　This　allowed　C-nZVI　to　overcome　most　of　the　inherent　defects　of　nZVI　and　had　ideal　abilities　to　resist　agglomeration,　acid　corrosion,　and　oxidation.　Same　as　the　traditional　Fenton-like　reaction,　the　generation　of　hydroxyl　radicals　(·OH)　and　superoxide　radicals　(·O2–)　was　the　main　way　for　C-nZVI　to　degrade　17β-E2.　The　ligands　as　the　ions　transport　channel　further　stimulated　the　excitation　of　·OH　and　·O2–,　and　the　singlet　oxygen　(1O2)　was　also　found　to　play　a　role　in　the　latter　part　of　the　reaction.　However,　C-nZVI　had　a　special　mechanism　of　first　coupling　between　citrate　ligands　and　17β-E2,　as　well　as　subsequent　degradation　by　ROSs,　which　might　be　the　reason　why　C-nZVI　has　a　much　faster　degradation　efficiency　than　the　general　nZVI.　And　the　degradation　process　of　17β-E2　showed　its　four　rings　might　be　destroyed　one　by　one　starting　from　the　benzene　ring.　Therefore,　this　heterogeneous　Fenton　system　assisted　by　chelating　agent　ligands　has　a　certain　value　for　the　research　of　water　emergency　restoration.　©　2021　Elsevier　B.V.