Abstract: The development trend of large-scale wind turbine blades in batches, standardization, high precision and high performance put forward higher requirements on the mold material, design and precision manufacturing technology of wind turbine blade, however, the systematic research still lacks. In this research, the skin structure, steel frame structure, and characteristics and synergistic effect of the skin-steel frame connection part are summarized combining with the actual forming process by the blade mold. The research provides intuitive data reference for the engineering prediction and control.