Date palm seeds (Phoenix dactylifera L.) were investigated as a biosorbent for removal of Pb(II) ions, which has a toxic effect on the environment. A batch sorption process was applied. Optimization of Pb(II) biosorption ontodate palm seedswas successfully carried out using response surface methodology. The effects of process variables, such as pH, initial Pb(II) concentration and biosorbent mass, on the adsorbed amount of Pb(II) were investigated using Box-Behnken design. The fitted results were found to be in good agreement with the results obtained by performing the experiments. The second-order response function showed that pH and initial Pb(II) concentration had positive effects, while biosorbent mass showed a negative effect. Initial Pb(II) concentration was the most significant factors that affected the removal of Pb(II) under the studied conditions. The maximum uptake of Pb(II) predicted by optimization plots was 24.07 mg/g at pH 5 initial Pb(II) concentration 100 mg/L and biosorbent mass 0.100 g.