Abstract: A series of adsorbents synthesized from chitosan-grafted-methacrylic acid/acrylamide/sodium allyl sulfonate (CTS-g-MAA/AM/SAS) composite hydrogels with various amounts of SAS were prepared. The effects of particle size, dosage of composite hydrogel, the pH value and initial concentration of Cu2+ in solution on the adsorption capacity were investigated. The results showed that a adsorption capacity of the CTS-g-MAA/AM/SAS composite hydrogels was increased with the increasing of pH value. A maximum absorption amount of Cu2+ of 823 mg/g was observed using 0.1 g/25 mL absorbent with particle size of 0.074-0.2 mm under pH value of 6.0. Freundlich, Langmuir plots and their isotherm coefficients for the adsorption of Cu2+ indicated a multilayer adsorption behavior using this adsorbent.