A fuel cell has a structure that an area of an opening at which a first flow passage opens toward a diffusion layer side of a fuel electrode is smaller than an area of an opening at which a second flow passage opens toward the diffusion layer side. This structure serves as a supply suppression structure for suppressing supply of liquid fuel from the first flow passage to the diffusion layer of the fuel electrode, and a discharge acceleration structure for accelerating discharge of discharge gas from the second flow passage. As compared with the case where the opening area of the first flow passage and the opening area of the second flow passage are equal to each other, the supply of liquid fuel from the first flow passage to the diffusion layer is suppressed so that liquid fuel is more easily filled in the first flow passage.