Provided is a solid oxide fuel cell (SOFC), including: a fuel electrode for allowing a fuel gas to be reacted; an air electrode for allowing a gas containing oxygen to be reacted; an electrolyte film provided between the fuel electrode and the air electrode; and a reaction prevention film provided between the air electrode and the electrolyte film. The porosity of the reaction prevention film is less than 10%, particularly preferably “closed pore-ratio” is 50% or more. The diameter of closed pores in the reaction prevention film is 0.1 to 3 μm. The reaction prevention film includes closed pores each containing a component (e.g., Sr) for the air electrode. This can provide an SOFC in which a decrease in output due to an increase in electric resistance between an air electrode and a solid electrolyte film hardly occurs even after long-term use.