A chisel includes a hammered portion to be hammered which is provided so as to project from a middle or an end of a handle and extend to pass through a portion on an extended line in the direction opposite to the direction of the blade. Even if the chisel is hammered in a state where a tip of the blade thereof is not inserted into a bone, the chisel easily advances in the direction of the blade, thereby reducing a possibility that the blade slides on a surface of the bone.
