The present disclosure relates to a communication method and system for converging a 5th-Generation (5G) communication system for supporting higher data rates beyond a 4th-Generation (4G) system with a technology for Internet of Things (IoT). The present disclosure may be applied to intelligent services based on the 5G communication technology and the IoT-related technology, such as smart home, smart building, smart city, smart car, connected car, health care, digital education, smart retail, security and safety services. The disclosure proposes, when a UE is registered in an AMf which does not support ATSSS (registration procedure), a method by which, an old AMF identifies the registration and releases an MA PDU session and a method by which the UE identifies the registration and releases the MA PDU session in a wireless communication system according to an embodiment.