An IP address management method, wherein the method comprises: receiving, by a mobile node, MN (160, 1600), after accessing an IP subnet on which an IP address anchor is located, switchover indication information sent by the IP address anchor; and determining, by the MN (160, 1600) according to the switchover indication information, whether the accessed IP subnet has changed the switchover indication information comprising an IP address prefix allocated by the IP address anchor, an IP address prefix allocated by another IP address anchor, and a type identifier, wherein the type identifier is used to differentially identify the IP address prefix allocated by the IP address anchor and the IP address prefix allocated by the another IP address anchor; and the determining, by the MN (160, 1600) according to the switchover indication information, whether the accessed IP subnet has changed comprises: determining, by the MN (160, 1600), whether the IP address prefix allocated by the IP address anchor meets a preset condition, wherein the preset condition is: the IP address prefix allocated by the IP address anchor does not exist in previous switchover indication information received by the MN (160, 1600), or the IP address prefix allocated by the IP address anchor exists in previous switchover indication information received by the MN (160, 1600) and is identified as being allocated by the another IP address anchor; and if the IP address prefix allocated by the IP address anchor meets the preset condition, determining, by the MN (160, 1600), that the accessed IP subnet has changed; or if the IP address prefix allocated by the IP address anchor does not meet the preset condition, determining, by the MN (160, 1600), that the accessed IP subnet has not changed. receiving, by a mobile node, MN (160, 1600), after accessing an IP subnet on which an IP address anchor is located, switchover indication information sent by the IP address anchor; and determining, by the MN (160, 1600) according to the switchover indication information, whether the accessed IP subnet has changed the switchover indication information comprising an IP address prefix allocated by the IP address anchor, an IP address prefix allocated by another IP address anchor, and a type identifier, wherein the type identifier is used to differentially identify the IP address prefix allocated by the IP address anchor and the IP address prefix allocated by the another IP address anchor; and the determining, by the MN (160, 1600) according to the switchover indication information, whether the accessed IP subnet has changed comprises: determining, by the MN (160, 1600), whether the IP address prefix allocated by the IP address anchor meets a preset condition, wherein the preset condition is: the IP address prefix allocated by the IP address anchor does not exist in previous switchover indication information received by the MN (160, 1600), or the IP address prefix allocated by the IP address anchor exists in previous switchover indication information received by the MN (160, 1600) and is identified as being allocated by the another IP address anchor; and if the IP address prefix allocated by the IP address anchor meets the preset condition, determining, by the MN (160, 1600), that the accessed IP subnet has changed; or if the IP address prefix allocated by the IP address anchor does not meet the preset condition, determining, by the MN (160, 1600), that the accessed IP subnet has not changed. determining, by the MN (160, 1600), whether the IP address prefix allocated by the IP address anchor meets a preset condition, wherein the preset condition is: the IP address prefix allocated by the IP address anchor does not exist in previous switchover indication information received by the MN (160, 1600), or the IP address prefix allocated by the IP address anchor exists in previous switchover indication information received by the MN (160, 1600) and is identified as being allocated by the another IP address anchor; and if the IP address prefix allocated by the IP address anchor meets the preset condition, determining, by the MN (160, 1600), that the accessed IP subnet has changed; or if the IP address prefix allocated by the IP address anchor does not meet the preset condition, determining, by the MN (160, 1600), that the accessed IP subnet has not changed.