Abstract: Carbon neutral technology has become one of the most effective solutions for thermal power generation.HR3C austenitic heat-resistant steel has become a typical material for high-temperature components used in ultra-supercritical units because of its excellent high-temperature performance. SEM, TEM and EBSD techniques were used to observe the microstructure of the unserved samples and samples with 35564 h and 67705 h of service, respectively, while the room temperature tensile and high temperature tensile properties of several materials were measured. The results show that HR3C heat-resistant steel has good high-temperature stability, and the grain structure is consistent with that of the unserved sample.The tensile properties and tensile properties do not change significantly with the non-serviced samples at room-temperature and high-temperature.