PURPOSE: To provide a wind mill vane without resistance sound caused by wind pressure by bending one long side of an oblong trapezoidal plate shape wind mill vane in a range of 90-155° in the wind pressure applied direction according to the purpose.

CONSTITUTION: One long side of an oblong trapezoidal plate shape wind mill vane is bent 10 a range of 90-155° in the wind pressure applied direction according to the purpose to form a vane to be used in this wind mill, and four vanes of such shape assembled with the inclination of 30° to form rotary vane are assembled to a shaft. With the long side being thus bent in the wind pressure applied direction, the convection change of air is provided to eliminate resistance sound caused by wind pressure.