Based on the CFD method, the aerodynamic performance of the IEA Wind 15 MW horizontal axis wind turbine under extreme operating gust conditions is analyzed. The finite element model of 15 MW wind turbine blade is established by using ANSYS APDL software to define the composite layer scheme. Based on Workbench platform, the modal analysis and static analysis of wind turbine blade are carried out to study the influence of extreme operating gust on the structural performance of wind turbine blade. The results show that the extreme operating gust has a great influence on the aerodynamic performance and blade structure performance of the wind turbine. The time points of the extreme value of the wind turbine thrust and torque are later than the extreme value of the wind speed. The flow separation area along the blade span is positively correlated with the wind speed. During the extreme gust, the displacement of the blade gradually increases from the root to the tip of the blade. The maximum stress of the blade appears in the main beam of the blade and is 0.6R away from the root of the blade. At the same time, the displacement and maximum stress of the blade tip change greatly in a short time, which will increase the probability of blade failure.