A fuel cell system (100) comprises: a hydrogen generator (1) for generating fuel gas by a reforming reaction using a raw fuel; a fuel cell (7) for generating electric power by use of the fuel gas; a combustor (2) for heating the hydrogen generator (1); an open/close valves (9A, 9B) for opening or closing a gas flow path (9) for supplying the gas delivered from the hydrogen generator (1) to the combustor (2); a combustion air supplier (4) for supplying combustion air to the combustor (2); an ignitor (5) provided in the combustor (2); and a controller (30). The combustor (2) is configured so as to combust using the gas supplied from the gas flow path (9) while the fuel cell (7) is generating electric power. When the combustor (2) misfires while the fuel cell (7) is generating electric power, the controller (30) executes the ignition operation of the ignitor (5) while the open/close valves (9A, 9B) are maintained to be open.
