Preserving method and device for virtual network

Disclosed in an embodiment of the present invention is a preserving method for a virtual network. The method comprises: receiving, by a network device (for example, a transmission controller), a request message for establishing a virtual network topology, the request message for establishing the virtual network topology carrying a resource parameter of the virtual network and/or a preserving recovery type of the virtual network; according to the resource parameter of the virtual network and/or the preserving recovery type of the virtual network, reserving operation physical resources and preserving physical resources from idle physical resources of a physical network; mapping virtual links in the virtual network to the operation physical resources and the preserving physical resources. The above technical solution enables the virtual network to have a preserving capability, such that when a failure occurs in the physical network corresponding to the virtual network, a preserving replacement can be rapidly performed on the physical network without affecting the virtual network, and the topology of the virtual network does not change, thus improving user experience.