The present invention relates to a main shifting device which operates the transmission which is the electric transmission of a combine. The main shifting device for the transmission of the combine includes a lever unit including a main shifting lever which is rotated around a lever hinge of a bracket and connected to a plurality of link devices for operating an HST type continuously variable transmission which is a hydraulic driving method of the transmission according to the forward and backward rotation of the main shifting lever around the lever hinge. The present invention includes a potentiometer which is formed on one side of the bracket to sense the rotation displacement of the main shifting lever; and a motor which is formed on the other side of the bracket and driven by controlling signals of a main CPU which received an electric resistance value of the potentiometer. The upper parts of the link devices are connected to an output shaft of the motor. As operation parts of the main shifting lever and
