A fuel cell generates electric power when the solid oxide type fuel cell element is arranged in a flame or in a position close to the flame, and the durability of the fuel cell is high. A fuel cell 10 for generating electricity when the solid oxide type fuel cell, in which a cathode layer is formed on one face of a solid electrolyte layer and an anode layer is formed on the other face of the solid electrolyte layer, is arranged in a flame or in a position close to the flame, wherein the solid electrolyte layer is made of porous material, the porosity of which is not less than 10%, so that cracks are not caused in the solid electrolyte layer by a sudden temperature change in the solid oxide type fuel cell when the solid oxide type fuel cell is arranged in the flame or in a position close to the flame or when the solid oxide type fuel cell is separated from the flame or the position close to the flame.