The present disclosure relates to a pre-5th-Generation (5G) or 5G communication system to be provided for supporting higher data rates beyond 4th-Generation (4G) communication system such as long-term evolution (LTE). Disclosed is radio access technology (RAT) switching in a wireless communication system, and an operating method of a server for managing a session comprises the steps of: receiving information related to a determination on the switching of a RAT; determining, on the basis of the information, whether the RAT for providing a service to a terminal is switched from a first RAT to a second RAT; and transmitting, to an object for processing a user plan, a message indicating that a data route of the terminal will be switched from the first RAT to the second RAT.