The utility model discloses an adjustable three-ball finishing barrel comprising a barrel body provided with three mounting holes. A steel ball is arranged in each of the mounting hole, and a spring is arranged on the steel ball in the mounting hole; and the bottom part of the barrel body is in thread connection with an alloy pressure plate. With the adjustable three-ball finishing barrel, an irregular fish top can be milled and shaped, and irregular fish top junks can be fished; the finishing barrel provides a grabbing force during fishing to guarantee the finishing of junks without collars or shoulders, has large fishing range, and can be adjusted timely and fish junks with contractive diameters.