New radio (NR) power headroom report (PHR) design for millimeter wave (mmWave) deployment is discussed. The power control process for mmWave may include beam-specific periodic PHR reporting and user equipment (UE)-specific event-trigger PHR reporting. The periodic PHR reporting may either provide a single PHR that includes power headroom information for each of the serving beams, or the UE may be configured to measure and report PHR for different beams in different slots. When reporting a single PHR with power headroom information for multiple serving beams, a beam index may be included in the reserved bits of the PHR. For the event-trigger PHR, the PHR reported based on a detected event trigger may provide power headroom information only for the current serving beam, or for all serving beams.