A characteristic recovery apparatus is provided with a DMFC having anode and cathode electrodes; anode-side and cathode-side separators for feeding the anode and cathode electrodes with pure water or a solution and an oxygen-containing gas, respectively; a voltage-applying means for forcing current to flow between the electrodes in the same direction as a direction of current flow during power generation of the fuel cell; and a control means for controlling the voltage-applying means.