A fuel cell comprising cathode catalyst layer (2); anode catalyst layer (3); proton conduction film (6) interposed between the cathode catalyst layer (2) and the anode catalyst layer (3); liquid fuel tank (9) for storing of liquid fuel (L); fuel vaporization layer (10) for feeding volatile components of the liquid fuel to the anode catalyst layer (3); and vaporized fuel accommodation chamber (12) interposed between the fuel vaporization layer (10) and the anode catalyst layer (3), characterized in that the fuel cell further comprises internal pressure escape means (20) for discharging any carbon-dioxide-containing gas produced by the anode catalyst layer (3) through a side wall of the vaporized fuel accommodation chamber (12) to the outside of the cell.
