Ag2O nanoparticles anchored on the Mg(OH)2 nanoplates (Ag2O@Mg(OH)2) were successfully prepared by a facile one-step method, which combined the Mg(OH)2 formation with Ag2O deposition. The synthesized products were characterized by a wide range of techniques including powder X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and nitrogen physisorption analysis. It was found that Ag2O nanoparticles anchored on the Mg(OH)2 nanoplates show good dispersion and less aggregation relative to the single Ag2O nanoaggregates. In addition, iodide (I-) removal by the Ag2O@Mg(OH)2 nanocomposite was studied systematically. Batch experiments reveal that the nanocomposite exhibits extremely high I- removal rate (