A simple and green method has been developed for in situ assembly of magnetic Fe3O4 on the pillared bentonite by a solvothermal reaction. Fe3O4 nanopaticles have a nearly uniform size of about 200 nm, and they create the homogeneous structures distributed on the bentonite surface. The resulting magnetic material (Fe3O4@Al-B) has a surface area of 110 m(2)/g and a saturation magnetization of 36.18 emu/g. At the same time, Fe3O4@Al-B has a strong surface affinity toward microcystin-LR (MC-LR) both in Mili-Q water and river water samples. Adsorption of MC-LR on Fe3O4@AI-B increases with pH decrease, with a maximum adsorption at pH 2.1. The equilibrium adsorption data are also analyzed by using the Langmuir and Freundlich models to evaluate the adsorption capacity of Fe3O4@AI-B and a result of 161.29 mg/g is achieved. The pseudo-second-order kinetic model provides the best correlation of the experimental data. Therefore, Fe3O4@Al-B is an effective technology and has a great potential in removing MC-LR from drinking water resources. (C) 2013 Elsevier B.V. All rights reserved.