Abstract: Laser welding is affected by the coupling of multiple physical fields and the nonlinear response of materials. The constructed weld response surface model is difficult to characterize the complex thermal mechanical metallurgical coupling behavior, which affects the accurate expression of the model on the actual welding process and cannot provide feedback for parameter optimization, making it difficult to achieve optimal parameter combinations and poor welding results. Therefore, a study on the optimization of laser welding process parameters for cracks in wind turbine blade structures is proposed. Using finite element models to simulate stress, temperature, and deformation during laser welding processes, providing physical field data for subsequent steps; Based on the finite element simulation results, a weld response surface model is constructed through grey correlation analysis to characterize the actual welding situation of the process; A parameter optimization function is constructed with the goal of minimizing weld defect rate and maximizing weld strength. The Whale Optimization Algorithm (CWOA) based on chaotic search strategy is used to iteratively optimize process parameters, and the optimal combination of crack laser welding process parameters for wind turbine blade structure response is determined. The experimental results show that the proposed method can effectively optimize the laser welding process parameters, significantly improve the quality of crack welding, reduce the defect rate, and achieve good application effects.