Disclosed are a composition for an electrode binder of a capacitive deionization apparatus including at least one a hydrophilic polymer and a bifunctional cross-linking agent having a hydroxy group or a carboxyl group at both terminal ends, and at least one anion exchange group therein, and the bifunctional cross-linking agent being cross-linkable with the at least one hydrophilic polymer, an electrode for a capacitive deionization apparatus including the composition, a capacitive deionization apparatus including the electrode, and a method of removing ions from a liquid by using the capacitive deionization apparatus.