Abstract: Based on the roughness tolerance of airfoil,the distributed roughness element was simulated by 3D modeling method to replace the traditional rough band,and the roughness model was printed by 3D printing technology. Through wind tunnel test,the aerodynamic performance of 18% thickness airfoil with rough leading edge was obtained. The test results proved that the lift coefficients improved with the increase of Reynolds numbers. Rough leading edge leads to lower maximum lift coefficient,higher drag coefficient,lower maximum lift-drag ratio,and earlier stall angle of attack. Meanwhile,compared with the leading edge bump,the leading edge pit roughness has less influence on the aerodynamic performance of the wind turbine airfoil.