FUEL CELL SYSTEM

A fuel cell system that can prevent impurities from intensively collecting near inlets of fuel cells. The fuel cell system includes a fuel cell stack formed by stacking fuel cells, each fuel cell having a power generation portion, a stack manifold with a fuel gas inlet communication hole disposed at an end of the fuel cell stack in the stacking direction of the fuel cells, a mixed gas supply channel communicating with the fuel gas inlet communication hole for supplying a mixed gas of a fuel gas and fuel off-gas to the fuel cell stack, a stirring mixer for swirling the mixed gas provided in the mixed gas supply channel, and a guide rib provided on the inner wall of the fuel gas inlet communication hole of the stack manifold, on the side opposite to the side of the power generation portions of the fuel cells.