NOVELTY - A cathode material preparing method involves mixing praseodymium nitrate hexahydrate, cobalt(II) nitrate hexahydrate, strontium nitrate, ferric nitrate nonahydrate and citric acid. The mixture is stirred in a stirring device. The resulting solution is placed in a baking box when the solution becomes brown gel and dried to make the brown gel become brown powder. The brown powder is roasted. The roasted product is subjected to X-ray diffraction phase test to display the structure of sample. The conductivity of calcium titanium oxide of praseodymium-strontium-cobalt-iron oxide is tested.    USE - Method for preparing a cathode material of medium-temperature solid oxide fuel battery.    ADVANTAGE - The method enables effectively preparing the cathode material of medium-temperature solid oxide fuel battery with better electronic and ion conductivity, thus improving the dissociating capacity and the absorbing capacity of the oxygen, and improving transmission efficiency of the electrons.    DETAILED DESCRIPTION - A cathode material preparing method involves weighing 15.2553 weight% of praseodymium nitrate hexahydrate, 11.6412 weight% of cobalt(II) nitrate hexahydrate, 3.1745 weight% of strontium nitrate, 4.04 weight% of ferric nitrate nonahydrate and 21.014 weight% of citric acid, where mole ratio between the citric acid and the metal cathode (praseodymium (Pr3+), strontium (Sr2+), cobalt (CO3+), iron (Fe3+)) is 1.2:1. The nitrates are mixed and stirred in a stirring device after dissolved with deionized water. The resulting solution is placed in a baking box when the solution becomes brown gel and dried for 3 hours at 120 degrees C to make the brown gel become brown powder. The brown powder is taken out and roasted for 6 hours at 900 degrees C. The roasted product is subjected to X-ray diffraction phase test to display the structure of sample, when the structure of the sample same with the single-phase calcium titanium mine, calcium titanium oxide of praseodymium-strontium-cobalt-iron oxide (Pr1-xSrxCo(0.8)Fe(0.2)O(3- delta )) is acquired, where x is 0.2-0.6. The conductivity of calcium titanium oxide of praseodymium-strontium-cobalt-iron oxide is tested, in which the testing result shows that the material is used as the cathode material of medium-temperature solid oxide fuel battery.