In this study, effects of ionic radius, charge, and mass on the electro sorption desalination performance of activated carbon electrodes were investigated. The sorption capacity of carbon electrodes was approximately 0.08-0.18 mmol/g carbon. The electro sorption capacity of monovalent ions was higher than multivalent ions. Covering area of cation on electrode is smaller than anion, when considering Covering area of hydrated ions, the cation and anion is almost equal. Because of the relatively small pore diameter (2 nm) of the carbon electrode, only 15.62 to 37.90 m2/g carbon surface area was available to ions eletro sorption.