Abstract: Turbine blade interdisciplinary design involves coupling among multiple disciplines such as aerodynamics, structures, heat transfer, and strength. With the continuous increase in turbine inlet temperatures of aero-engines, traditional design methods face severe challenges. Conventional engineering methods typically adopt a sequential and decoupled design process for disciplines (including aerodynamics, heat transfer, and strength), applying various simplifications to computational models and methods. This paper conducts a multidisciplinary coupled simulation study focusing on the first-stage rotor blade of a two-stage turbine. To ensure the reliability of the verification method, grid independence verification and experimental validation of the turbine blade cooling effectiveness were first performed. Subsequently, a comparison was made between the results from the multidisciplinary coupled simulation method and those from the conventional engineering methods. The findings indicate that: in terms of aerodynamic performance calculation, the coupled simulation method and the engineering method show good consistency, with differences in all aerodynamic parameters (stage expansion ratio, stage efficiency, first-stage rotor full-annulus inlet/outlet flow rates, first-stage rotor inlet/outlet absolute Mach numbers, etc.) being within 1.30%. The temperature field distribution exhibits non-uniform differences, with blade surface temperature discrepancies of 0.41% (maximum), –7.63% (minimum), and –4.89% (average). In strength calculations, the differences in maximum radial displacement and axial displacement of the blade body are –10.20% and –7.24%, respectively, while the maximum discrepancy in vibration characteristic frequencies (static and dynamic frequencies) is 1.50%. These differences primarily arise because the multidisciplinary coupled simulation method is based on high-fidelity geometric models and fully three-dimensional computational techniques, retains detailed structures such as film cooling holes, and better accounts for the multi-field coupling effects of aerodynamics, thermodynamics, and structures, thereby providing an effective approach for the design of air-cooled turbine blades.