Provided is a method of power control, repeater and storage medium. The repeater is used to amplify cellular communication signals between a base station and a user equipment. The method includes measuring a power of downlink signals received from the base station; estimating a power of uplink signals transmitted from the user equipment, wherein the power of uplink signals is estimated based on the measured power of downlink signals and a power constant, and the power constant is an estimated closed-loop power control constant between the power of downlink signals and the power of uplink signals; and determining a power of uplink signals transmitted to the base station, based on the estimated power of uplink signals. In this method, AGC (Auto Gain Control) can respond quickly and properly, thereby reducing the false response of AGC and improving the repeater performance.