Water pollution because of inorganic contaminants is a seri- ous problem due to the acute toxicities and carcinogenic nature of pollutants. Recently, much attention has been focused on using natural and low-cost adsorbents, especially food residues, for removing toxic metal ions. Batch removal of nickel (Ni(II)), lead (Pb(II)), and cadmium (Cd(II)) from aqueous solution using a natural adsor- bent is described in this study. Effects of various parameters on adsorption capacities such as pH, adsorbent dose, and stirring time were investigated by batch experiments. The maximum adsorption capacities for Ni(II), Pb(II), and Cd(II) ions were 1.6 mg g-1, 125 mg g-1, and 84 mg g-1, respectively. Characterization of the surface modification was per- formed with FTIR measurements. FTIR spectra showed that chemi- sorption takes place at the sur- face of the adsorbent. The Freundlich and Langmuir adsorp- tion isotherms were used to eval- uate the equilibrium data. The characteristic parameters for each isotherm were determined. The Langmuir and Freundlich isotherm provided the best corre- lation for Ni(II), Cd(II), and Pb(II) using banana peel.