A separator includes a first plate and a second plate. The separator has a first fuel gas supply unit, a second fuel gas supply unit, first sandwiching sections, second sandwiching sections, a first case unit and a second case unit. A fuel gas supply passage extends through the first fuel gas supply unit and the second fuel gas supply unit in a stacking direction. The first sandwiching sections are connected to the first fuel gas supply unit through first bridges, and the second sandwiching sections are connected to a second fuel gas supply unit through first bridges. The first sandwiching sections and the second sandwiching sections sandwich electrolyte electrode assemblies. Each of the first sandwiching sections and the second sandwiching sections sandwich electrolyte electrode assemblies. Each of the first sandwiching sections has a fuel gas inlet and each of the second sandwiching sections has an oxygen-containing gas inlet. The first case unit and the second case unit have oxygen-containing gas supply units. The first case unit is connected to the first sandwiching sections through second bridges, and the second case unit is connected to the second sandwiching sections through second bridges. Oxygen-containing gas supply passages extend through the oxygen-containing gas supply units in the stacking direction.