Ten control and ten diabetic subjects were first given a baseline session of no temperature biofeedback, and then were exposed to four 40-minute temperature biofeedback sessions over consecutive days. As the result of feedback training, peripheral skin temperatures increased on the training (right) hands of both groups, and this occurred to a greater extent in the diabetic group. Concomitant temperature increases occurred also in the left hands of both groups. Neither group produced any significant changes in heart rate, respiration rate, or systolic blood pressure with the exception of a significant decrease in diastolic blood pressure for the diabetic group. No difference in diastolic blood pressure was observed, however, when the diabetics were compared with the control group. The results would suggest further evaluation of temperature biofeedback training is warranted in a diabetic population as a potential means of increasing peripheral blood flow in the extremities.