This application provides a communication method and a network device. The communication method includes: obtaining, by a first network device, one or more priorities of one or more network slices in a first network slice set for providing a service to an application; and sending, by the first network device, a correspondence between the one or more priorities and the one or more network slices in the first network slice set to a second network device, where a terminal route selection policy on a terminal is updated based on the correspondence.