A method of controlling a threshold for detecting peaks of physiological signals includes: obtaining a physiological signal measured from a person being examined; determining whether a peak of the physiological signals is detected based on a result of comparing the physiological signals with a threshold; and controlling the threshold based on a minimum threshold and either the threshold or a feature value of the detected peak based on a result of the determining. When a threshold for detecting peaks of physiological signals is controlled, even if an interval between the peaks is irregular or there is a large difference in values of the peaks, the peaks can be accurately detected.