A method of transmitting, by a user equipment, UE, power measurement information related to beam reporting in a wireless communication system, the method comprising: reporting, to a base station, LTE capability information; receiving downlink control information, DCI, triggering reporting of the power measurement information; receiving a downlink reference signal for the reporting of the power measurement information; and transmitting, to the base station, the power measurement information determined based on the received downlink reference signal, wherein based on the reporting of the power measurement information being configured for Layer 1 reference signal received power, L1-RSRP, reporting: a minimum required time for the reporting of the power measurement information is determined based on (i) a first timing parameter related to a first time duration from a last timing of the downlink reference signal to a transmission timing of the power measurement information and (ii) a second timing parameter related to a second time duration from a timing of a triggering DCI to a timing of the downlink reference signal, wherein information regarding the second timing parameter is reported as the UE capability information, wherein, for a subcarrier spacing of 60 kHz or 120 kHz, the minimum required time for reporting of the power measurement information is calculated as a sum of (i) the first timing parameter and (ii) the second timing parameter if, depending on the value of the second timing parameter, the sum of (i) the first timing parameter and (ii) the second timing parameter does not exceed a specific threshold value, and the minimum required time for reporting of the power measurement information is otherwise determined based on a preset upper bound value. reporting, to a base station, LTE capability information; receiving downlink control information, DCI, triggering reporting of the power measurement information; receiving a downlink reference signal for the reporting of the power measurement information; and transmitting, to the base station, the power measurement information determined based on the received downlink reference signal, wherein based on the reporting of the power measurement information being configured for Layer 1 reference signal received power, L1-RSRP, reporting: a minimum required time for the reporting of the power measurement information is determined based on (i) a first timing parameter related to a first time duration from a last timing of the downlink reference signal to a transmission timing of the power measurement information and (ii) a second timing parameter related to a second time duration from a timing of a triggering DCI to a timing of the downlink reference signal, wherein information regarding the second timing parameter is reported as the UE capability information, wherein, for a subcarrier spacing of 60 kHz or 120 kHz, the minimum required time for reporting of the power measurement information is calculated as a sum of (i) the first timing parameter and (ii) the second timing parameter if, depending on the value of the second timing parameter, the sum of (i) the first timing parameter and (ii) the second timing parameter does not exceed a specific threshold value, and the minimum required time for reporting of the power measurement information is otherwise determined based on a preset upper bound value.