Abstract: During the phased array ultrasonic testing of wind turbine blades with pultrusion beam, the signal is affected by the special structure of the blade and the anisotropy of its material, resulting in the low signal-to-noise ratio of the data, and the defect identification is difficult in the data analysis. To solve this problem, this paper analyzes the structure and typical defects of wind turbine blades with pultrusion beam, clarifies the corresponding relationship between phased array ultrasonic image signal and the structure of wind turbine blades with pultrusion beam, and proposes an efficient and accurate analysis process. After verification, this method helps to improve the quality of data analysis work in the wind power industry.