An axisymmetric parameterized high pressure turbine (HPT) casing model was established after HPT casing structure was analysed. Based on the thermal-structure coupling deformation and parameter sensitivity analysis result

12 key structure parameters were selected as optimization variables. Taking the casing mass and the hook area average radial displacement as the multi-objective function

the second generation non-dominated sorting genetic algorithm (NSGA-Ⅱ) was adopted to solve this multi-objective optimization problem. The optimization result showed that the optimal strengthening ribs structure was more efficient at heat conduction

and other optimal structure was more efficient at losing weight. After the optimization

the model weight and radial displacement were lessened simultaneously.