The present disclosure relates to a communication technique for converging an IoT technology with a 5G communication system for supporting a higher data transmission rate beyond a 4G system, and a system therefor. The present disclosure may be applied to an intelligent 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 safety related service, or the like) on the basis of a 5G communication technology and an IoT related technology. A method and an apparatus for reselecting a beam and selecting a suitable beam to be camped on, by a terminal, in order to be provided with a service in a next generation mobile communication system operating on the basis of a beam.