PURPOSE: To obtain a high-temperature fuel cell cathode material, excellent in oxidation resistance and stability at a high temperature, which shows a stable phase in an unchanged crystalline structure even in a high temperature range near the operating temperature of a high-temperature fuel cell while maintaining electric conductivity and has no change in thermal expansion coefficient.

CONSTITUTION: Cathode material has composition as shown by a general expression, (La1-xMx)1-y MnOz, where A is Sr, Ca or Ba, and O≤x≤0.4, 0<y≤0.15, and z>(xy-x-3y+6)/2 hold. It is constituted by annealing treatment material under a corresponding firing material oxidizing atmosphere at 600°C or more. The cathode material is formed by firing lanthanum manganate group material which may contain alkaline earth metal compound and then giving annealing treatment in an oxidizing atmosphere such as in the air at 600°C, preferably at 800-1400°C. A time for the annealing treatment is usually 3-60hours.