1. A method of auditory evoked heart rate variability analysis comprises the following steps of: stimulating the auditory system of a person by a sound through a sound transmission device; capturing an electrocardiogram signal of the person; performing analog-to-digital conversion of the electrocardiogram signal; selecting the peaks of the electrocardiogram signal and transforming the qualified peaks to a heartbeat cycle curve; performing a spectrum analysis to the peak signal; and obtaining the difference of the spectral parameters before and after the evoked sounds.