The purpose of this study were to investigate the differences in velocity of postural sway between normal and older adults and to examine the change of velocity of postural sway through Transcutaneous Electrical Nerve Stimulation(TENS) applied to the posterior aspect of the legs. Fourteen normal adults(4 men and 10 women) and Fourteen older adults(6men and 8 women) were tested while standing on a force platform under four conditions; eye opened, eye closed, eye opened with TENS, and eye closed with TENS were applied in a random order. Prior to testing, adhesive TENS electrodes were fastened to the skin overlying the left and right medial and lateral bellies of the gastrocnemius muscles. The results indicate that the application of TENS brought about a decrease in postural sway as expressed by average sway velocity, in addition to a decrease in medio-lateral and anterior-posterior sway velocity. The application of low-amplitude TENS to the lower limbs in normal and older adults decreases postural sway during stance. In conclusion, the application of TENS to older adults whose somatosensory were deteriorated decreases medio-lateral postural sway velocity and is possible to decrease riskiness of a fall at all.