The present disclosure relates to a communication scheme and system for converging a 5th generation (5G) communication system for supporting a data rate higher than that of a 4th generation (4G) system with an internet of things (IoT) technology. The present disclosure is applicable to intelligent services (e.g., smart home, smart building, smart city, smart car, connected car, health care, digital education, retail, and security and safety-related services) based on the 5G communication technology and the IoT-related technology. The present disclosure provides a method for preventing a legacy terminal from camping on an enhanced LTE (eLTE) base station that is connected to only a next generation (NG) core by combining a legacy information element (IE) and a new IE carried in system information broadcast by the base station in a next generation mobile communication system.