The adsorption of Pb (II) ions onto chitosan beads and cross-linked chitosan beads has been investigated. The epichlorohydrin (ECH) was used as a cross-linking agent. Experiments were carried out as a function of pH, stirring time, adsorbent dosage and concentration of Pb (II) ions. The experimental data of the adsorption equilibrium from Pb (II) solution correlated well with the Langmuir isoth...