There is provided a microbial fuel cell that can inhibit oxygen from dissolving in a liquid through the surface to increase electrical energy recovery efficiency. The microbial fuel cell according to the present invention comprises a liquid comprising organic matter; an anode placed in the liquid comprising the organic matter; an air cathode having an air intake portion for taking air into the air cathode; and an oxygen-blocking portion for blocking oxygen from dissolving in the liquid comprising the organic matter through the liquid surface of the liquid comprising the organic matter.
