To provide a cutting blade capable of eliminating the need for sharpening work by solving a problem in which a bush cutting function of a peripheral cutting blade is blunted and abraded due to bush cutting work rotation such as mowing to cause inability of bush cutting, and therefore the sharpening/grinding work is forced.SOLUTION: Even if a peripheral cutting blade is abraded due to a bush cutting abutment article, a portion of circumference of through-holes 21, 22, 23, 24, 25 provided in the peripheral cutting blade of a bush cutting blade is abraded and eliminated by the bush cutting abutment article and is opened. As a result, the through-holes 21, 22, 23, 24, 25 become a new cutting blade, each through-hole of the other through-holes after the rotation similarly becomes a new cutting blade sequentially, and therefore the need of sharpening work is eliminated.SELECTED DRAWING: Figure 1【課題】草刈り等の刈り払い作業回転により外周刃の刈り払い機能が鈍磨して、刈り払い切断不能に至り、刃立て研削作業を余儀なくされるが、この刃立作業を不要とする刈刃を提供する。【解決手段】刈り払い当接物により外周刃が摩耗しても、刈り払い刃の外周刃に設けた貫通孔２１、２２、２３、２４、２５の周囲一部が刈り払い当設物に摩耗除去されて開口し、その貫通孔２１、２２、２３、２４、２５が新切断刃となり、その回転後位のその他の各貫通孔もまた同様、順次、新切断刃となるため、刃立て作業を不要になる。【選択図】図１
