A communication scheme and a system thereof for converging an internet of things (IoT) technology and a fifth generation (5G) communication system for supporting a high data transmission rate beyond that of a fourth generation (4G) system are provided. The disclosure may be applied to a smart service (e.g., a smart home, a smart building, a smart city, a smart car or connected car, healthcare, digital education, retail business, a security and security related service, or the like) based on a 5G communication technology and an IoT related technology. The disclosure relates to a method and an apparatus for supporting a terminal to set up connection to a network in a next generation mobile communication system.