Vibrotactile thresholds for a 20Hz and a 150Hz stimulus were determined during high-frequency (100Hz) transcutaneous electrical nerve stimulation (TENS) of 13-minutes duration. TENS was applied either at a site proximal or distal to the probe of the vibrator at an intensity which was strong enough to elicit muscle activity. TENS applied at a distal site had no marked effect on vibrotactile thresholds either for a 20Hz or 150Hz stimulus. However, TENS applied at a proximal site caused a marked threshold elevation for both frequencies studied. Present results suggest that vibrotactile threshold elevation produced by high-frequency TENS is due to peripheral electrogenic blockade, presumably an antidromic invasion of vibration receptors.