At present, the study and application of the ferro-rare earth series metals are very active and vigorous in the field of alloy materials, mainly covering: hydrogen storage material, permanent-magnet material, magnetic recording material, magneto-optic recording material, magneto-striction material, etc. If the above materials are made into thin films, they will certainly find wider applications in many fields, which has attracted great attention of scientists and engineers at home and abroad. Now the metal films of the ferro-rare earth series metal are generally prepared by the physical vapour-phase deposition technologies,such as vacuum vapour deposition, cathode sputtering and ion plating.Obviously, their cost is relatively high and their productivity is low, unfavourable for industrial production in large scale. Here we present a method for preparing alloy films of the ferro-rare earth series metal by electrodeposition. At present, the study and application of the ferro-rare earth series metals are very active and vigorous in the field of alloy materials, mainly covering: hydrogen storage material, permanent-magnet material, magnetic recording material, magneto-optic recording material, magneto -striction material, etc. If the above materials are made into thin films, they will certainly find wider applications in many fields, which has attracted great attention of scientists and engineers at home and abroad. Now the metal films of the ferro-rare earth series metal are generally prepared by the physical vapor-phase deposition technologies, such as vacuum deposition, cathode sputtering and ion plating. Obviously, their cost is relatively high and their productivity is low, unfavorable for industrial production in large scale. Here we present a method for preparing alloy films of the ferro-rare earth series metal by electrodeposition.