Abstract: Under the new situation,in response to the national ’’carbon peak,carbon neutral’’ call,ultra-clean emission units above 600 MW are bound to become the main models in thermal power enterprises. As the power pillar at the end of the power grid in northern Fujian,the 2×660 MW ultra-supercritical thermal power unit of Fujian Huadian Shaowu Energy Co.,Ltd.,Phase III project not only makes important contributions to energy saving and emission reduction,but also plays an important role in power grid stability and livelihood protection. By summarizing the experience of each start-up process of the unit since it was put into operation in 2018,the stable operation of the unit and the extreme hot start in a short time after tripping were analyzed. It puts forward targeted measures and matters needing attention,which can provide reference for the same type units to start up in extreme hot state in the future.