A nuclear power plant includes a nuclear reactor containment structure housing a nuclear reactor, a pressure vessel containing condensed water therein and having a receiving space located lower than a bottom of the containment structure, a release pipe connecting the containment structure to the pressure vessel such that water vapor and fission products generated in the containment structure in the event of an accident is capable of flowing into the pressure vessel, and a recovery pipe connecting the pressure vessel to the containment structure such that the condensed water received in the pressure vessel is capable of flowing into the containment structure. When a level of the condensed water received in the pressure vessel is higher than a water level in the containment structure, the condensed water flows from the pressure vessel toward the containment structure by a water head difference.