Abstract: Taking the 1.5 MW wind turbines blade as a model,the influence of the external environment on the performance of the wind turbines is analyzed by the method of blade data acquisition and experimental analysis. The blade of the wind turbines is simulated by bladed software. The results show that the change of temperature and height has a certain influence on the change of atmospheric density and atmospheric viscosity. The change of lift drag ratio is caused the change of air density and the change of Renault number mainly is caused atmospheric viscosity. Therefore,the change of temperature and height has a common effect on the aerodynamics of wind turbines. The research is helpful to the design and development of wind turbines and to reduce the failure rate of wind turbines during operation.