The rotor blade is an important device that converts kinetic energy of wind into mechanical energy. It affects power performance, efficiency of energy conversion, load and dynamic stability of a wind power generation system. This paper presents an aerodynamic design of 3 MW class blade using BEM and confirms that the design satisfies the initial design target by BEM and CFD analysis. To investigate the effects of radial flow at the inboard region, the result of static BEM analysis was compared with the result of CFD analysis. The result of quantitative comparison among thrust force, power coefficient and mechanical power depending on wind speed change is presented. Furthermore, design reference data such as pressure, streamline, torque and thrust force distribution on the blade surface is presented as well.