The present invention relates to a method for operating a steam power plant with a first turbine condenser (4) and a second turbine condenser (6) which are connected in series on the cooling water side, wherein the temperature (t1) and the pressure (p1) of the exhaust steam (3) in the first turbine condenser (4) are higher than the temperature (t2) and the pressure (p2) of the exhaust steam (5) in the second turbine condenser (6), and the condensate is fed to at least two low pressure pre-heaters (11, 12, 13) that are connected in series. The aim of the present invention is to increase the efficiency of a steam power plant. Said aim is achieved in that a part (22) of the warm exhaust gas (3) of the first turbine condenser (4) is brought into contact with the cold condensate of the second turbine condenser (6) via an exhaust steam pump (21).