Supported Pt-Co-Cr alloy catalysts on graphitized carbon black showing increased activity and stability as electrode catalysts for oxygen-reduction reaction in phosphoric acid fuel cells have been developed by co-precipitation of the corresponding metal nitrates. XRD investigations showed that a tetragonal ordered structure was formed upon thermal treatment. The formation of this structure required temperatures above 873 K. Although two-step and other sequential methods are known for the preparation of such catalysts, the newly developed method described here will led more efficiently to catalysts, having a small particle size, of the platinum cobalt chromium alloy.