A fuel cell system includes a windshield washer container 1 storing windshield washer fluid, a permeable membrane unit 2 provided inside the windshield washer container 1, and a fuel cell 11. The permeable membrane unit 2 has the capability of extracting methanol from the windshield washer fluid. The extracted methanol is directly used as the fuel for the fuel cell 11. The windshield washer container 1 has the size comparable with or less than that of a conventional windshield washer container.