A session management function entity selection method includes receiving a reselection indication and information about a first session of user equipment UE from a first session management function entity, where the reselection indication is used to instruct to reselect a session management function entity; saving a correspondence between the first session management function entity and the information about the first session according to the reselection indication; receiving a session establishment request message, where the session establishment request message carries the information about the first session; determining a second session management function entity different from the first session management function entity; and sending a session management request to the second session management function entity.