Abstract: To analyze the influence of Gurney flaps on the aerodynamic performance and noise characteristics of wind turbine airfoils, the LES model in Fluent software was used to study the aerodynamic performance and flow field distribution of an original airfoil and the airfoil with Gurney flaps of different heights at the angle of attack in 4°-20°, while their far-field aerodynamic noise was calculated using Acoustics modules based on FW-H sound analogy method. Results show that when the lift coefficient of airfoil is greater than 0.8, the Gurney flap could effectively increase the lift coefficient, but would also raise its drag coefficient significantly. When the flap height is less than 3% of the chord length, the stalling angle of attack would be effectively increased; when the flap height exceeds 3% of the chord length, the increase degree of lift coefficient drops, while that of drag coefficient rises, and the aerodynamic noise increases sharply thereafter. The airfoil sound radiation shows the characteristics of dipole sound field.