The physiological signal measuring method includes the following steps: obtaining a user physiological signal； separating the user physiological signal into multiple first packets according to a first box number； performing a sifting process respectively on the first packets by Empirical Mode Decomposition (EMD) to obtain multiple temporal intrinsic mode functions (temporal IMFs) respectively corresponding to the first packets； calculating multiple average envelope curves according to multiple upper envelope curves and multiple lower envelope curves respectively corresponding to the temporal IMFs； averaging the average envelope curves to generate a semi-IMF； calculating at least one correlation coefficient according to the semi-IMF and at least another semi-IMF； when the at least one correlation coefficient is larger than a correlation coefficient threshold, determining at least one signal section corresponding to the at least one correlation coefficient as at least one main component section of the user physiological signal.
