FUEL CELL SYSTEM

A fuel cell system includes: a fuel cell (34) generating electricity by using fuel and an oxidant gas; a housing (10a) storing the fuel cell; a ventilation fan (42) causing an inside of the housing to be ventilated; a flow state detection switch (60) arranged on a flow path of fluid which flows due to ventilation, and outputting an ON signal if the fluid flows and outputting an OFF signal if the fluid does not flow; and a controller (15) controlling at least the ventilation fan, wherein the controller controls quantity of drive of the ventilation fan, and includes a storage unit that stores a control command value of the ventilation fan as a switch control command value, and a setting unit that sets the minimum control command value of the ventilation fan based on the switch control command value stored in the storage unit.