Abstract: The present invention relates to a method for manufacturing a ruthenium oxide-supported catalyst for preparing chlorine, and more particularly, to a method for manufacturing a catalyst and a catalyst manufactured thereby, wherein the catalyst includes a ruthenium ingredient of which a support level on an outer surface of a support is significantly improved, and the use of the catalyst in preparing chlorine can provide a high conversion rate of chlorine even at a low reaction temperature. According to an embodiment of the present invention, the method for manufacturing a ruthenium oxide-supported catalyst for preparing chlorine may include the steps of: (a) dissolving a ruthenium compound in an organic solvent to prepare a solution and supporting the same on at least one support selected from titania and alumina; (b) performing drying thereon after the supporting; and (c) performing calcining thereon after the drying.