The invention discloses an adjustable copper bar, and belongs to the field of electrical components. The copper bar comprises a conductive plate, an insulated guide, terminals, a capacitance regulating panel and a drive mechanism; a terminal and an insulating guide rail are respectively fixed on the conductive plate, the insulating guide extends along one side of the conductive plate, a capacitance adjusting plate is slidably mounted on the insulated guide rail, and the capacitance regulating plate and the conductive plate are arranged parallel to each other, an insulating coating is arrangedon one side wall of the conductive plate, and the driving mechanism is insulatively connected with the conductive plate, and the driving mechanism is used for driving the capacitance regulating plateto move along the length direction of the insulating guide rail to change the projection area of the capacitance regulating plate on the conductive plate. The invention can adjust the self-provided capacitance value of the copper bar.