A large amount of iodine-containing solution (ICS) is produced in both nuclear medicine and the atomic energy industry, which may cause serious health hazards in case if it enters aquatic ecosystem without sufficient treatment. The treatment of ICS by silver demonstrates great potential for iodine capture and retention. Nano-scale silver and its oxide particles formed on the surface of Al₂O₃ via electroless plating was introduced to ICS treatment. A series of batch sorption experiments against ICS by Ag-Ag₂O modified Al₂O₃ (Ag-Ag₂O-Al₂O₃) has been conducted. Ag-Ag₂O-Al₂O₃ was characterized by SEM, FTIR, XRD, and XPS before and after the reaction. The results show that ~ 82.6% of I⁻ was removed by 4.0 g/L Ag-Ag₂O-Al₂O₃ from the solution containing 0.3 mg/L I⁻ at pH 3 and at 298 K. Ag-Ag₂O-Al₂O₃ was effective in low concentration artificial nuclear medical ICS treatment. Thermodynamic analysis showed that the reaction consistent with the Langmuir model and was a uniform exothermic reaction of a single layer. Therefore, Ag-Ag₂O-Al₂O₃ prepared by electroless plating could be considered as a potential material for the ICS treatment.