To provide a rotary blade for a brush cutter which is made lighter while securing strength to withstand use. SOLUTION: A plurality of continuously provided lightweight holes 16 having a shape capable of being filled in a plane between the center portion 10 of the rotary blade 2 and the blade portion 14 are provided in succession so as to reduce the weight while maintaining the strength of the rotary blade Improvement in shock absorbing power was realized. BACKGROUND OF THE INVENTION【課題】使用に耐える強度を確保しながら、より軽量化された刈払機用回転刃を提供する。【解決手段】回転刃2の中心部10から刃部14の間に平面充填可能な形状の軽量孔16を平面充填する態様で連続して複数個設け、回転刃の強度を維持しながら軽量化と衝撃吸収力の向上を実現した。【選択図】図1
