A knife and a lawn mower having the same are provided. The knife includes a main body. The main body includes a body portion and an assembling portion which are connected to each other. The assembling portion is for being disposed on a mowing disk of a lawn mower. The mowing disk is rotatable along an axial direction. The body portion includes two side faces opposite to each other. Each of the two side faces has a curved section and a plane section. A midline is defined between the two side faces. An angle is defined by the midline and a vertical plane which is transverse to the axial direction.本發明關於一種刀片及包括該刀片之割草機。該刀片包括一本體，該本體包括相連接之一身部及一組接部，該組接部供設於一割草機之一割草盤，該割草盤圍繞一軸向旋轉，該身部包括相對之二側面，各該側面設有一弧形段及一平面段，該二側面之間定義一中線，該中線與橫向該軸向之一垂直面之間具有一角度。
