A kind of blade of grass trimmer, it can be driven by a drive shaft and be rotated along a rotation center, the blade includes at least one cutting part, an and mounting portion being connect with the cutting part, there is the mounting portion basal wall connecting with the cutting part and at least one prominent with respect to the what basal wall and auxiliary adjacent to the rotation center to cut wall. Wall is cut using the auxiliary of the neighbouring rotation center and the opposite what basal wall protrusion, it can be during the blade rotates, the plant close to the rotation center is cut, to prevent plant to be wrapped in the drive shaft of the drive blade rotation, and ensures the smoothness of the blade when rotated.一種割草機的刀片，可被一驅動軸驅動並沿著一個旋轉中心轉動，該刀片包含至少一個切割部，以及一個與該切割部連接的安裝部，該安裝部具有一個與該切割部連接的基壁，以及至少一個相對於該基壁突出並鄰近該旋轉中心的輔助切割壁。利用鄰近該旋轉中心且相對於該基壁突出之輔助切割壁，可以在該刀片旋轉的過程中，切割靠近該旋轉中心的植物，以防止植物纏繞在帶動該刀片轉動的驅動軸上，並確保該刀片在旋轉時的順暢性。
