Electro-kinetic decontamination has been studied for radioactive concrete of nuclear power plants because of its effective removal of contaminants from deep inside concrete. Although many experiments have been conducted, a systematic comparison has been scarcely conducted. By a thorough review, this study reveals how different conditions of electro-kinetic decontamination changes the decontamination ratio and rate of Cs and Co. The tested conditions include cell configurations (i.e., geometry of concrete waste, electrode materials, and volume of solutions) and operating conditions (i.e., types and concentrations of solutions, electric field, and test duration). The careful analysis suggests the important roles of pH in electrolytic solution, electric field, and pre-treatment. We also discuss the chemical conditions under which the decontamination of Cs and Co was optimized in the presence of an applied voltage. In addition, we critically review the conditions of simulated concrete samples in the previous experiments in comparison with actual nuclear plant data. (C) The Author(s) 2018. Published by ECS.