A fuel cell system. The system (10) includes a FC (12), a TRC (26), an oxygen-containing gas supply apparatus (20), a battery (16), and an ECU (24). The ECU is capable of performing power consumptioncontrol which allows the oxygen-containing gas supply apparatus (20) to consume electrical energy during regeneration of the TRC (26). The ECU (24) is configured to determine a charge margin (72) with respect to a charge limitation value (Clim) of the battery (16), in a manner that the charge margin (72) set after the power consumption control starts becomes smaller than the charge margin (72) set before the power consumption control is performed.