A physiological information processing method includes: acquiring electrocardiogram data from a subject； acquiring pulse wave data from the subject； measuring a plurality of RR intervals based on the acquired electrocardiogram data； measuring a plurality of pulse wave transit times based on the acquired electrocardiogram data and the acquired pulse wave data； calculating, based on the measured RR intervals and the measured pulse wave transit times during a given time period, a parameter related to correlation between the measured RR intervals and the measured pulse wave transit times； and outputting the calculated parameter.
