The invention aims at disclosing a double-pressing plate fixing structure for the end part of a rotor winding of a large-scale alternating current excitation generator motor. The structure comprises end part pressing plates, bevel washers, fixing nuts, fixing bolts, fixing annular plates and fixing devices. The end part pressing plates are positioned on the outer side of the end part of the rotor winding for fixing the end part of the rotor winding; the fixing bolts pass through the end part pressing plates and gaps at the cross positions of upper-layer winding bars and lower-layer winding bars of the rotor winding; and the rotor winding is fixed on the fixing device on the inner side of the rotor winding by the end part pressing plates and the fixing annular plates. The fixing device is of full circle welding structure; one fixing annular plate is arranged on the fixing device corresponding to each layer of end part pressing plate; each layer of fixing annular plate is provided with a through hole corresponding to the corresponding end part pressing plate, and thereby the corresponding fixing bolt can be fixed to the inner side of the fixing device after passing through the fixing annular plate. According to the structure, problems about fixation and protection of the end part of the rotor winding are effectively solved, and the unit can operate safely and stably.