A knocking tool comprises a handle having an inclined cambered groove; one end of the cambered groove being at a first end surface of the handle; the first end surface of the handle having at least one insertion hole; an outer lateral wall of the handle having at least one through hole which is communicated to the respective insertion holes; and at least one joint assembled to the first end surface of the handle; one surface of the joint being installed with at least one insertion rod which is inserted into the insertion holes; a retainer being inserted into the respective through hole so as to tightly engage the insertion rod to the insertion hole. A connecting rod is assembled to the insertion groove of the handle; and one end of the connecting rod has a combining portion. The combining portion is formed with combining holes.