A fuel cell system (10, 200) includes an intake pipe (45, 46) that admits an introduction of oxidizing gas upstream of an oxidizing gas supply source that supplies the oxidizing gas to a fuel cell (20), and an exhaust pipe (51, 52, 221, 222) that discharges exhaust gas which contains a vapor generated at an oxygen electrode side through an operation of the fuel cell (20). The fuel cell system (10, 200) is provided with a circulating pipe (61, 62, 220) that connects the intake pipe and the exhaust pipe (51, 52, 221, 222), a circulating valve (60) that is provided in the circulating pipe and operated to adjust a flow rate of the exhaust gas supplied from the exhaust pipe (51, 52, 221, 222) to the intake pipe, and a pressure generating member that is provided in the exhaust pipe (51, 52, 221, 222) at a position at which the circulating pipe and the exhaust pipe (51, 52, 221, 222) are joined and generates a pressure that is higher than at least an atmospheric pressure.