This low-pressure condenser is provided with: a pressure bulkhead which partitions the inside of the container into an upper space and a lower space; a heat transfer tube which is arranged in the upper space; and a reheater which is arranged in the lower space and which, by means of high-temperature steam flowing from the outside into the lower space, heats water which condenses in the upper space and flows into the lower space. The reheater includes multiple partition members, a receiving plate which receives water flowing downward via the partition members, and a dam which is connected to the outer peripheral edge of the receiving plate. The lower ends of the multiple partition members are below the upper end of the dam.