The invention relates to a quick-assembly conversion cutter rod, and belongs to the technical field of electric tools. The quick-assembly conversion cutter rod is mainly formed by arranging a guide rod, a cutting sleeve and a chuck, wherein the cutting sleeve and the chuck are connected with the guide rod; a rod handle which is in matching connection with electric tools is arranged at the rear end of the guide rod; a chuck turnover groove and a rectangular chute and a turnover hole which can slide back and forth are formed on the front section of the guide rod; a steel ball through hole and a steel ball positioning hole are formed on the guide rod; the chuck consists of a chuck body, a steel ball support fixing sleeve, a steel ball support and a spring; symmetrical bulged cylinders and square shafts are arranged on the chuck body, and the square shafts are mutually perpendicular to the cylinders; an axial hole for installing the tools is formed at each cylinder end; the steel ball support fixing sleeve, the steel ball support and the spring are arranged on the cylinders; and a steel ball for locking the tools is arranged between a waist-shaped hole of the axial hole wall and a steel ball hole on the steel ball support. The quick-assembly conversion cutter rod has a scientific and reasonable structure, and is easy to manufacture and convenient to use. The two tools can be arranged simultaneously by one guide rod, and two cutters can be converted quickly during operation, so the work efficiency is improved, and labor strength is reduced.