A cutting blade piece protective structure that prevents an obstacle from coming into direct contact with a blade portion of a cutting blade piece, saving light weight, saving a replacement cost at the time of breakage, and inhibiting lawn mowing performance by the cutting blade piece, is provided, and the lawn mower that includes the blade disk to be rotationally driven and at least one cutting blade piece attached to the outer peripheral portion of the blade disk, a blade guard for preventing an obstacle from coming into contact with the blade portion of the cutting blade piece is provided on the cutting blade piece. Preferably, the blade guard is attachable to and detachable from the cutting blade piece.
