Sulfide-modified　zero-valent　iron　(S-nZVI)　has　been　shown　to　be　an　effective　material　for　removal　of　various　contaminants　from　wastewater.　However,　the　release　of　this　powder　material　into　the　environment　brings　some　hidden　troubles　to　its　application.　Therefore,　poly(sodium　acrylate)-poly(acrylamide)　(PANa-PAM)　hydrogel　was　used　in　this　study　to　capture　S-nZVI　particles　within　their　frameworks,　and　encapsulate　them　from　being　released　into　the　environment.　The　structure　and　composition　characterization　of　the　composites　(S-nZVI@H)　showed　that　the　S-nZVI　particles　were　tightly　encapsulated　by　the　cross-linked　network　frameworks　of　the　PANa-PAM　hydrogel.　The　content　of　Fe　in　S-nZVI@H　was　123.77　mg/g,　and　only　6.34%　were　leached　out　after　being　used　three　times　in　a　row.　The　maximum　removal　capacity　of　Cr(VI)　by　S-nZVI@H　was　9.24　mg/g.　Moreover,　S-nZVI@H　showed　excellent　reusability　and　stability.　The　proposed　mechanism　of　Cr(VI)　removal　by　S-nZVI@H　can　be　described　as　uptake-reduction-codeposition.　The　synergistic　effect　of　PANa-PAM　hydrogel　and　S-nZVI　particles　realized　stabilization　and　solidification　of　Cr(VI).　These　results　demonstrate　that　the　encapsulation　of　S-nZVI　particles　by　PANa-PAM　hydrogel　not　only　limited　their　leakage　to　the　environment,　but　also　facilitated　the　removal　of　Cr(VI).　©　2023　The　Institution　of　Chemical　Engineers