An embodiment of the present disclosure provides an operating method of a Session Management Function (SMF) entity in a wireless communication system. The operating method may include receiving, from an Access And Mobility Management Function (AMF) entity, a Protocol Data Unit (PDU) session creation request message, receiving, from a Unified Data Management (UDM) entity, subscriber information associated with a session of a user equipment (UE), transmitting, to the AMF entity, a response message with respect to the PDU session creation request message, selecting a Policy Control Function (PCF) entity, transmitting, to the selected PCF entity, a session management policy information creation request message comprising Session Migration Information, receiving, from the PCF entity, policy information about a PDU Session which is determined based on a maximum bitrate (MBR) value (UE-Slice-MBR) corresponding to a slice for the PDU Session, and selecting a User Plane Function (UPF) entity to support session continuity by considering an MBR, based on the policy information about a PDU Session.