We have prepared a novel kind of magnetic nanoparticle with high adsorption capacity and good selectivity for Pb2+ ions by modifying the magnetic nanoparticles with polyvinyl alcohol (PVA) and thiourea. The resultant magnetic nanoparticles were used to adsorb Pb2+ ions from aqueous solution. The influence of the solution pH, the adsorption time, the adsorption temperature, coexisting ions, and the initial concentration of Pb2+ ions on the adsorption of Pb2+ ions were investigated. The results indicated that Pb2+ ions adsorption was an endothermic reaction, and adsorption equilibrium was achieved within 30 min. The optimal pH for the adsorption of Pb 21 ions was pH 5.5, and the maximum adsorption capacity of Pb2+ ions was found to be 220 mg/g. Moreover, the coexisting cations such as Ca2+, Co2+, and Ni2+ had little effect on adsorption of Pb2+ ions. The regeneration studies showed that thiourea functionalized PVA-coated magnetic nanoparticles could be reused for the adsorption of Pb 21 ions from aqueous solutions over five cycles without remarkable change in the adsorption capacity. (C) 2014 Wiley Periodicals, Inc.