A multistage pressure condenser comprising: a plurality of chambers with different pressures; a pressure bulkhead (4,34) that has a plurality of holes and that divides a low-pressure chamber, which is one of the chambers at low pressure, in a vertical direction; a cooling-tube bank that is provided in an upper section of the low-pressure chamber partitioned by the pressure bulkhead (4,34) and that performs heat exchange with low-pressure steam guided to the low-pressure chamber by coolant introduced therein so as to condense the low-pressure steam to low-pressure steam condensate; a reheat chamber that serves as a lower section of the low-pressure chamber partitioned by the pressure bulkhead (4,34) and that stores the low-pressure steam condensate falling from the holes in the pressure bulkhead (4, 34); high-pressure-steam introducing means for introducing high-pressure steam within a high-pressure chamber, which is one of the chambers at high pressure, to the reheat chamber; a plurality of plate members (10,20,40) that are arranged parallel to each other below the pressure bulkhead (4,34), characterized in that the plurality of plate members extend in a falling direction of the low-pressure steam condensate falling from the holes in the pressure bulkhead (4,34), in that each of the plurality of plate members (10,20,40) has a corrugated shape including leftward and rightward facing projections and recesses that are repeatedly arranged in the vertical direction, and in that the adjacent plate members (10,20,40) are arranged away from each other at a distance to allow the low-pressure steam condensate falling from the holes to contact both of the adjacent corrugated plate members (10,20,40) to form a liquid film therebetween. a plurality of chambers with different pressures; a pressure bulkhead (4,34) that has a plurality of holes and that divides a low-pressure chamber, which is one of the chambers at low pressure, in a vertical direction; a cooling-tube bank that is provided in an upper section of the low-pressure chamber partitioned by the pressure bulkhead (4,34) and that performs heat exchange with low-pressure steam guided to the low-pressure chamber by coolant introduced therein so as to condense the low-pressure steam to low-pressure steam condensate; a reheat chamber that serves as a lower section of the low-pressure chamber partitioned by the pressure bulkhead (4,34) and that stores the low-pressure steam condensate falling from the holes in the pressure bulkhead (4, 34); high-pressure-steam introducing means for introducing high-pressure steam within a high-pressure chamber, which is one of the chambers at high pressure, to the reheat chamber; a plurality of plate members (10,20,40) that are arranged parallel to each other below the pressure bulkhead (4,34), characterized in that the plurality of plate members extend in a falling direction of the low-pressure steam condensate falling from the holes in the pressure bulkhead (4,34), in that each of the plurality of plate members (10,20,40) has a corrugated shape including leftward and rightward facing projections and recesses that are repeatedly arranged in the vertical direction, and in that the adjacent plate members (10,20,40) are arranged away from each other at a distance to allow the low-pressure steam condensate falling from the holes to contact both of the adjacent corrugated plate members (10,20,40) to form a liquid film therebetween.