Chitosan was chemically modified with glycidylmethacrylate and ethylenediamine or diethylenetriaminein a two-step reaction. Firstly, opening of the three-ring of glycidylmethacrylate, leaving a double a bond for further reaction. Finally, produced product was reacted through the free glycidylmethacrylate double bond with ethylenediamine or diethylenetriamine. The chemicallymodified chitosan were characterized by elemental analysis, IR, 13C-NMR, XRD, SEMand employed for barium, manganese, cobalt, nickel, copper, zinc and cadmiumbiosorption. Elemental analysis data based on nitrogen atom content gave an incorporation oforganic pendant groups to the modified chitosan. 13C-NMR and FT-IR results are in agreement with the success of the proposed chemical modification. The metal sorption capability of the final chelating material was higher than chitosandue to the increment of basic centers attached to the pendant chains. The experimental data were adjusted toLangmuir, Freundlich and Temkin sorption isothermmodels. The behavior suggested that this new modified biopolymer could be employed as a promising sorbent for cation removal from polluted dye bath.