The specific adsorption of radiolabeled anions (sulfate, chloride) from perchlorate supporting electrolyte on gamma -Al2O3 powder has been investigated. It was demonstrated that a measurable adsorption occurs only at pH values under pH 6, The adsorption capacity of a given amount of gamma -Al2O3 powder tends to a limiting value with decreasing pH, A Langmuir-like adsorption isotherm describes the concentration dependence of the adsorption of sulfate species. It was found that the experimental results are very similar to those obtained in the case of hematite,