Abstract: An exhaust re-combustion type combined cycle power generation plant comprises a gas turbine plant, a boiler connected to the gas turbine plant, in which an exhaust gas from the gas turbine plant is heated, a steam turbine plant connected to the boiler and provided with a condensate and feed water system and a low temperature reheat system, in which the heated exhaust gas from the boiler is supplied to the condensate and feed water system as a heat source, a cooling steam supply system connected to the low temperature reheat system and adapted to supply a cooling steam to the high temperature section of the gas turbine plant, and a cooling steam recovery system connected to the high temperature section for recovering the cooling steam after cooling the high temperature section to an intermediate stage of an intermediate turbine of the steam turbine plant.