Abstract: The austenitic heat-resistant steel TP347H is widely used in heating tubes of thermal power unit boilers. Combining the service performance of austenitic heat-resistant steel tubes and the failure cases of TP347H steel tube bursts, the six common failure mechanisms, including intergranular corrosion, stress corrosion cracking, microstructure aging, oxidative corrosion, original defects and martensite transformation, of TP347H steel heating tubes during boiler operation are reviewed. The failure characteristics, analysis methods and preventive measures are described.