An apparatus for measuring an impedance of a fuel cell, the apparatus being used for a system that includes a fuel cell, a secondary battery, and a load device connected to the fuel cell and the secondary battery, the apparatus comprising: an AC power supply unit (531, 532) configured to output an AC current to the fuel cell; an AC adjusting unit configured to adjust the AC current so that a positive-electrode side AC potential difference matches a negative-electrode side AC potential difference, the positive-electrode side AC potential difference being a difference between an electric potential of the fuel cell on a positive electrode side and a middle electric potential, the negative-electrode side AC potential difference being a difference between an electric potential of the fuel cell on a negative electrode side and the middle electric potential, the middle electric potential being an electric potential at a midpoint between a positive electrode and a negative electrode of the fuel cell; an impedance calculating unit configured to calculate an impedance of the fuel cell on the basis of the adjusted AC current and at least one AC potential difference of the positive-electrode side AC potential difference and the negative-electrode side AC potential difference; characterized by an impedance adjusting unit configured to adjust the impedance of the fuel cell so that an impedance obtained by synthesizing an impedance of a route between the fuel cell and the load device and the impedance of the fuel cell becomes higher than an impedance obtained by synthesizing an impedance of a route between the secondary battery and the load device and the impedance of the fuel cell at a frequency of the AC current outputted from the AC power supply unit (531, 532). an AC power supply unit (531, 532) configured to output an AC current to the fuel cell; an AC adjusting unit configured to adjust the AC current so that a positive-electrode side AC potential difference matches a negative-electrode side AC potential difference, the positive-electrode side AC potential difference being a difference between an electric potential of the fuel cell on a positive electrode side and a middle electric potential, the negative-electrode side AC potential difference being a difference between an electric potential of the fuel cell on a negative electrode side and the middle electric potential, the middle electric potential being an electric potential at a midpoint between a positive electrode and a negative electrode of the fuel cell; an impedance calculating unit configured to calculate an impedance of the fuel cell on the basis of the adjusted AC current and at least one AC potential difference of the positive-electrode side AC potential difference and the negative-electrode side AC potential difference; characterized by an impedance adjusting unit configured to adjust the impedance of the fuel cell so that an impedance obtained by synthesizing an impedance of a route between the fuel cell and the load device and the impedance of the fuel cell becomes higher than an impedance obtained by synthesizing an impedance of a route between the secondary battery and the load device and the impedance of the fuel cell at a frequency of the AC current outputted from the AC power supply unit (531, 532).