FUEL CELL

A fuel cell includes: a membrane electrode gas diffusion layer assembly; a frame member which surrounds the membrane electrode gas diffusion layer assembly; and a pair of separators with the frame member and the membrane electrode gas diffusion layer assembly sandwiched therebetween. The separators include a manifold hole through which a reaction gas is supplied or discharged. The frame member includes a manifold opening which communicates with the manifold hole, an in-plane opening in which the membrane electrode gas diffusion layer assembly is disposed, a gas flow path which communicates with the in-plane opening and the manifold opening, a seal portion which is welded to the separators around the gas flow path, and an accommodation portion which is provided between the seal portion and the gas flow path to accommodate a material of the frame member caused to flow by welding.