A solid electrolytic fuel cell having an oxygen electrode layer on one surface of a solid electrolytic layer, having a fuel electrode layer on the other surface thereof, and having a reaction-preventing layer comprising a sintered body of an oxide between the upper surface of the solid electrolytic layer and the oxygen electrode layer for preventing elements from diffusing from the oxygen electrode layer into the solid electrolytic layer, wherein the oxygen electrode layer has a two-layer structure including an inner layer on the side of the reaction-preventing layer and a surface layer on the inner layer; the surface layer of the oxygen electrode layer comprises a sintered body of a perovskite composite oxide; and the inner layer of the oxygen electrode layer comprises a sintered body of a mixture of particles of an oxide for preventing the diffusion of elements and particles of the peroviskite composite oxide, and is formed more densely than said surface layer. The fuel cell has a decreased interfacial resistance between the oxygen electrode layer and the reaction-preventing layer, an increased junction strength between the oxygen electrode layer and the reaction-preventing layer, and generates electricity of a large output.