Abstract: With the deepening reform of the national power system, the competition of power generation enterprises is becoming increasingly fierce, and the development trend of large capacity, high parameters and low energy consumption is inevitable. In this paper, an ultra supercritical fossil-fuel power station is taken as the research object, LTD. The third phase of million kilowatts thermal power project as the research object, through ascension, the reheat steam temperature to study the ways to achieve reduces the overall energy consumption, so as to improve the core competitiveness of thermal power units. Unit in order to improve the main and reheat steam temperature, two different retrofit scheme is proposed in this paper, through the comparison on the advantages and disadvantages of the two different schemes, finally determine the main and reheat steam temperature ascension retrofit scheme, achieve the expected effect, realized the unit safe and economic operation of design value, worthy of the same type thermal power unit popularization and application.