Vibrotactile threshold was measured daily for four days at the dorsum of the middle finger, foot, and great toe in men undergoing maintenance hemodialysis twice weekly and in 12 controls. In uremic subjects, vibrotactile threshold at the great toe was correlated with age. Vibrotactile threshold was greater in the lower extremities in both groups and was increased at the toe and foot and marginally elevated at the finger in uremic patients compared to controls. Vibrotactile threshold at the toe and foot transiently decreased following a single hemodialysis. Thus, vibrotactile threshold is more impaired in the lower than in the upper extremity in uremia; this abnormality may be affected by both neuron length and the neurotoxin concentration in plasma. Vibrotactile threshold may have value as an indicator of neurological function and clinical status in uremia.