A　cellulose-g-poly-(acrylamide-co-sulfonic　acid)　polymeric　bio-adsorbent　(CASA)　was　prepared　by　grafting　copolymerization,　and　used　to　adsorb　Cr(III)　from　leather　wastewater.　The　SEM,　XRD,　FTIR,　and　XPS　results　showed　that　CASA　contains　many　spherical　particles　and　functional　groups　such　as　–NH2,　–C[dbnd]O,　and　–HSO3.　The　adsorption　experiments　revealed　that　CASA　presented　excellent　adsorption　performance　for　Cr(III)　(274.69　mg/g　of　max　adsorption　capacity)　from　high-salinity　wastewater,　which　was　much　better　than　other　reported　adsorbents　with　different　structures.　Meanwhile,　adsorption　equilibrium　could　be　reached　within　10　min　due　to　the　introduction　of　abundant　sulfonic　acid　groups　on　its　surface.　In　addition,　the　adsorption　process　followed　the　Langmuir　adsorption　isotherm,　and　the　experimental　data　conformed　to　the　pseudo-second-order　kinetics　model.　Moreover,　the　main　adsorption　mechanisms　include　chelation,　electrostatic　interactions,　and　cation　exchange,　which　provide　an　important　theoretical　basis　for　the　removal　of　toxic　inorganic　pollutants　from　leather　wastewater.　©　2021　Elsevier　Ltd