Abstract: The tips of the first-stage rotor blades in heavy-duty gas turbines often suffer damage such as ablation and cracking due to excessive thermal load concentration and large temperature gradients in these regions. Taking the first-stage rotor blades of a heavy-duty gas turbine as the research object, an initial layout scheme combining grooved tips with film holes was established based on tip leakage flow, heat transfer characteristics and temperature distribution. Subsequently, the film hole positions were optimized using a Kriging surrogate model combined with genetic algorithm, and the optimized scheme was validated through thermo-mechanical coupling analysis. Results show that the optimized scheme reduces the maximum tip temperature from 1 220.67 K to 1 167.95 K with a decrease exceeding 50 K, while effectively improving the temperature distribution at the pressure-side shoulder. The optimized scheme prevents cold gas waste and stress concentration. This study provides theoretical foundations and engineering references for optimizing cooling structures at the tips of rotor blades in heavy-duty gas turbines.