Method and device for efficient communication in next generation mobile communication system

The present invention relates to a communication technique for converging a 5G communication system to support a higher data transmission rate, higher than that of a 4G system, with IoT technology, as well as an associated system. . The present invention can be applied to a smart service (for example, smart homes, smart buildings, smart cities, smart cars or connected cars, healthcare, digital education, retail, safety and security services, etc.) based on 5G communication technology and technology associated with IoT. The present invention relates to a method of a terminal, the method comprising the steps of: determining a propagation loss reference beam on the basis that information indicating the propagation loss reference beam is received or no ; acquire a propagation loss based on the propagation loss reference beam; acquire a power margin (PH) on the basis of the propagation loss; and transmitting a power margin ratio (PHR) including the PH.