This paper presents the adsorption of Cu(II) ions from aqueous solution on modified Unye bentonite. Adsorption of Cu(II) ions by magnesium oxide-coated bentonite (MCB) sample was investigated as a function of the initial Cu (II) concentration, solution pH, ionic strength, temperature and inorganic ligands (Cl-, SO42-, and HPO42-). Changes in the surfaces and structure were characterized by means of XRD and N-2 gas adsorption data. The Langmuir monolayer adsorption capacity of MCB in 0.1 M KNO3 solution was estimated as 58.44 mg/g. Delta G, Delta H and Delta S values were evaluated for MCB to be -9.50 kJ/mol (at 303 K), 43.81 kJ/mol and 175.85 J/mol K. (C) 2010 Elsevier B.V. All rights reserved.