The present disclosure relates to a communication method and system for converging a 5th-Generation (5G) communication system for supporting higher data rates beyond a 4th-Generation (4G) system with a technology for Internet of Things (IoT). The present disclosure may be applied to intelligent services based on the 5G communication technology and the IoT-related technology, such as smart home, smart building, smart city, smart car, connected car, health care, digital education, smart retail, security and safety services.An improved method and an apparatus for reporting Power Headroom (PH) of a UE are provided. The Power Headroom Report (PHR) method of the present invention includes determining whether to trigger PHR based on a change of Power Management Maximum Power Reduction (P-MPR) between two time points, generating, if PHR is determined to be triggered, Power Headroom, and reporting the Power Headroom information to a base station.