There is provided a fuel cell unit and a fuel cell stack including a flow rate controlling member provided in an anode flow path on the side of an exhaust flow path so as to be in contact with an anode gas diffusion layer wherein the flow rate controlling member generates pressure difference between an upstream side of the fuel flow path from a portion at which the flow rate controlling member is provided and a downstream side of the fuel flow path from the portion at which the flow rate controlling member is provided. The fuel cell unit and the fuel cell stack can uniformly supply a fuel and can prevent backflow of the fuel containing an impurity gas from a downstream side.