A chitosan/polyvinyl alcohol (CTN/PVA-Fe3O4) magnetic composite was prepared in one step and examined by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy-energy dispersive X-ray analysis (SEM-EDX), transmission electron microscopy (TEM), dynamic light scattering (DLS), Brunauer-Emmett-Teller (BET), thermal gravimetric analysis/differential thermal analysis (TGA-DTA) and differential scanning calorimetry (DSC). Effects of several parameters, such as temperature, pH, and initial concentration on removal of Cu(II) from aqueous solution by the CTN/PVA magnetic composite were studied as a function of contact time. Equilibrium data obtained from sorption of Cu(II) solutions having initial concentrations of 25 to 400 mg L-1 by sorption of the CTN/PVA magnetic composite at different temperatures (25, 35 and 45 degrees C) were applied to Langmuir and Freundlich adsorption isotherms. Maximum adsorption capacity (Q(max))was found to be 143 mg g(-1) by using Langmuir isotherm model, by which thermodynamic parameters (Delta H degrees, Delta G degrees and Delta S degrees) were also calculated. Activation energy was calculated by using rate constants for this model and its value was found 26.52 kJ mol(-1). (C) 2017 Elsevier B.V. All rights reserved.