A method for measuring power of a received signal includes the following steps: determining N type(s) of sampling rate(s) of an analog-to-digital converter (ADC) according to a theoretical minimum sampling rate of the received signal; using the ADC to sample the received signal according to the N type(s) of sampling rate(s) within a period of sampling time and thereby obtaining sampling results; and measuring the power of the received signal according to the sampling results and the period of sampling time, wherein the theoretical minimum sampling rate is corresponding to a signal cycle of the received signal, the N is a positive integer, the N type(s) of sampling rate(s) is/are corresponding to N type(s) of sampling cycle(s), and any of the N type(s) of sampling cycle(s) and the signal cycle are coprime.