Abstract: From the perspective of ensuring structural reliability and safety, mechanical integrity analysis and validation methods of heavy-duty gas turbines were summarized. Based on material failure modes and damage mechanisms under severe service environments, the analyses of mechanical integrity, rotor and whole machine dynamics, and machine clearance design were conducted. The procedures and tasks of mechanical integrity analysis of gas turbine main components, the important role of testing and evaluation methods of mechanical integrity analysis, and the root cause analysis of the field issues on commercial units were systematically discussed, which can provide a complete set of verification and validation methods for reliability and safety of gas turbine structures.