Activated carbons were synthesized by thermochemical treatment of palm kernel shells (AC-PKS) and modified with ethylenediaminetetraacetic acid (AC-EDTA). The developed products were characterized by the surface area, porosity, and pH of point zero charge and were used for removal of Pb(II) ions from aqueous solution. The AC-PKS exhibited higher BET surface area (1559.9 m2/g) than the AC-EDTA (1100.7 m2/g). The influence of solution pH, adsorbent dose, initial Pb(II) ion concentration, and temperature on the removal of Pb(II) ions were examined and optimized. The adsorption of Pb(II) on AC-PKS and AC-EDTA fitted the pseudo-second-order kinetics model and the Langmuir model isotherm, respectively. The optimum conditions for sorption of Pb(II) were at the initial Pb(II) concentration of 150 mg/L, dosage 0.35 g (AC-PKS) and 0.25 g (AC-EDTA), and pH 4. Thermodynamic studies showed that the adsorption process was spontaneous and endothermic. The AC-PKS and AC-EDTA both demonstrated high Qmax of 80.6 mg/g and 104 mg/g, respectively, for Pb(II) adsorption. The adsorption data also fitted the Thomas fixed-bed adsorption model.