Abstract: The present invention relates to a cable spool with a damping brake, which has a modified central supporting axle with a combination of circular and square parts. The circular sectional part of the supporting axle is used for supporting the spool and the brake disk, the square sectional part at the axle end is used for fixing the brake clamps and for supporting to a fixture. The square sectional part at the middle of the axle will be mounted with a brake holder having square axle hole and a brake shoe. The brake force can be adjusted by a spring. During operation, the cable spool is pulled by an external force to release the cable, and a spool rib will immediately drive the brake disk, while the brake disk will be braked by the brake holder and the brake shoe. Once the external force stops pulling, the cable spool will stop rotating due to the brake force from the brake shoe. Therefore, the cable remaining on the spool will not release continually. No external power is needed to stop the spool.