A service switching method is used in a network that a service is switched to a protection path when a working path has failure, which includes the following steps: after a service end node detects the change of the network topology, it checks whether the failure working path has recovered to the normal, if yes, the service is switched from the protection path to the working path; if no, the flow ends. Also a network node for implementing the foregoing method is disclosed. It is not based on warning disappearing announce but based on the change of network topology that the scheme of the invention triggers the service switching process, so the diffusion of warning messages is reduced, and it can realize the backspace process when the protection path and the former working path have a part of sharing resource.