Cathode material and fuel cell

A fuel cell comprising:

• an anode,
• a cathode including a perovskite type oxide, the perovskite type oxide being expressed by the general formula ABO3 and including at least one of La and Sr at the A site, and
• a solid electrolyte layer disposed between the anode and the cathode,
• the cathode including a solid electrolyte layer-side region within 3 micrometers from a surface near to the solid electrolyte layer,
• the solid electrolyte layer-side region including a main phase comprising the perovskite type oxide, and a secondary phase comprising (Co,Fe)3O4 that includes both Co and Fe,
• an occupied area ratio of the secondary phase in a cross section of the solid electrolyte layer-side region being no more than 9.5%, and
• an occupied area ratio of the main phase in a cross section of the solid electrolyte layer-side region being at least 87.5%.