Abstract: In a process for continuously separating uranium isotopes, .sup.235 U and .sup.238 U, by oxidation-reduction chromatography using a column of an anion exchanger, the separation of uranium isotopes and the regeneration of the oxidizing agent and reducing agent both deactivated during the separation of uranium isotopes can be simultaneously effected in a single column by returning to and passing through the column of an anion exchanger having a uranium adsorption zone an eluate containing a deactivated oxidizing agent and a deactivated reducing agent to regenerate the deactivated oxidizing agent and the deactivated reducing agent and to form an oxidizing agent zone, and returning to and passing through the column the regenerated reducing agent for the reduction of uranium.