The invention relates to a method for making label allocation on ring network, calculating routing distance and implementing backup switching, and its kernel: separately allocting labels to node on ring network along clockwise and anticlockwise rings, respectively, and calculating routing distances between the node and lower-ring nodes, and based on the calculated results, respectively establishing corresponding relation between master and backup label exchange paths between the node and lower-ring node; when the master label exchange path fails, it switches the operating path to the backup label exchange path according to the corresponding relation. Thus, when adding / removing a node to / from a ring, the ring network can still operate; moreover, it is based on MPLS and transmits messages by the shortest path, thus raising transmitting efficiency; it can run failure detection protocol between adjacent nodes, thus increasing detecting and backup switching speeds; in addition, the invention supports inter-ring connection and connection with other MPLS networks.