A fuel cell includes a cell structure including a first electrode, a second electrode, and an electrolyte layer, a gas diffusion layer disposed adjacent to the first electrode, and a gas channel plate disposed adjacent to the gas diffusion layer, in which the gas diffusion layer is formed of a porous metal body having a three-dimensional mesh-like skeleton, the gas channel plate includes a first region including a first channel, a second region including a second channel, and a third region including a third channel, the first channel includes a slit extending from the center of the gas channel plate toward its outer edge at the boundary surface between the first region and the second region, letting the total area of the first channel at the boundary surface be a first opening area S1, letting the total area of the second channel at the boundary surface between the second region and the third region be a second opening area S2, and letting the total area of the third channel at the boundary surface between the third region and the gas diffusion layer be a third opening area S3, the relationship S2