Abstract: This paper discussed the development trend of ultra-supercritical units for power plant boilers in China and their requirements for materials. In response to this trend, researches on the key materials used in ultra-supercritical boilers were performed in Baosteel Iron & Steel Co. Ltd. Experiment data and materials production indicate that Baosteel is able to supply materials used in complete units for the key components of 600℃ ultra-supercritical boiler heating surfaces, such as water-cooled walls, superheaters and reheaters, which can displace the imported materials and narrow the gap between boiler materials in China and oversea. According to development requirements for 700℃ ultra-supercritical units in China, the selection, development and evaluation of materials used in high-temperature parts were carried out in order to support the development of domestic ultra-supercritical units.