The invention provides a collector ring balancing structure equipped with a water-cooled rotor. The collector ring balancing structure comprises a collector ring rotor, wherein a water inlet pipe is arranged in the collector ring rotor; the collector ring rotor is provided with collector rings and a fan; the collector ring rotor is connected with a magnetic pole lead; vent holes are arranged alongthe circumferential direction of each collector ring; and the collector ring balancing structure is characterized in that a solid arc segment free of the vent hole is arranged at the part, in a 180-degree symmetric direction of the magnetic pole lead, of each collector ring, thereby artificially generating unbalance in the opposite direction to offset the unbalance generated by the collector rings and the magnetic pole lead. According to the collector ring balancing structure equipped with the water-cooled rotor, through removing the vent holes of the collector rings and carrying out counterweight design on the collector ring rotor, the unbalance generated by the magnetic pole lead and the collector rings are offset, and vibration of an extended end is effectively improved.