The present disclosure relates to a communication technique for convergence of a 5G communication system for supporting a higher data transmission rate beyond a 4G system with an IoT technology, and a system therefor. The present disclosure can be applied to an intelligent service (for example, a smart home, a smart building, a smart city, a smart car or connected car, health care, digital education, retail business, security and safety-related service, etc.) on the basis of a 5G communication technology and an IoT-related technology. A communication method of a terminal in a mobile communication system according to an embodiment of the present specification comprises the steps of: acquiring cell-related information corresponding to a first communication mode; acquiring cell-related information corresponding to a second communication mode; receiving a first message through the second communication mode; and transmitting a request message corresponding to the first communication mode on the basis of the first message.