A ring network redundancy method is disclosed. If somewhere the connection of the ring network is damaged and broken, then the state of an initially blocked port that has been assigned as blocked is set as forward so as to keep the network functioning. And after the problem is repaired, a newly assigned blocked port is then assigned so that there is now once more a blocked ported; wherein the position of this newly assigned blocked port is set directly at one of the two ends of the repaired network line. Thereby the resettling time for the position of the newly assigned blocked port is reduced, thus the ring network system becomes much more stable.