A method and apparatus for protection switching in a ring network are provided. A method for protection switching in a ring network, which includes a first ring network having first and second connection nodes and a second ring network connected with the first ring network through the first and second connection nodes, includes: receiving, by the first connection node, first and second R-APS messages transmitted from nodes belonging to the first ring network; determining, by the first connection node, the position of closure in the first ring network by using the first and second R-APS messages and topology information; receiving, by the first connection node, a topology change signal transmitted from the second ring network; and transmitting, by the first connection node, an FDB flush message with reference to the position of closure.