A fuel cell system includes a fuel cell, a fluid passage for warming, a gas-liquid separator, a supply passage and a recirculating module. The fuel cell generates power with supply of a reaction gas. The gas-liquid separator separates moisture contained in an anode exhaust gas which is discharged from the fuel cell. The supply passage returns the anode exhaust gas, from which the moisture has been separated by the gas-liquid separator, to an inlet side of the reaction gas. The recirculating module mixes the anode exhaust gas, which is returned via the supply passage, with the reaction gas. The gas-liquid separator lies adjacent to the recirculating module, and the fluid passage for warming is disposed between the gas-liquid separator and the recirculating module.