Antioxidant activity and biological properties of ferulic acid (FA) are well recognized. This study was designed to estimate the potential utility of FA administered orally at low dosage for improvement of hyperglycemia in diabetes. With this aim we have evaluated the hypoglycemic effect of FA in two type diabetic animal models: (1) streptozotocin (STZ)-induced diabetic mice, a model of insulin-dependent diabetes mellitus (IDDM); (2) KK-Ay mice, a model of non-insulin dependent diabetes mellitus (NIDDM). In addition, we measured the production of thiobarbituric acid-reactive substances (TBARS) in brown adipose tissues of diabetic mice at the end of FA feeding experiment. FA at 0.01% and 0.1% of basal diet showed to suppress significantly blood glucose levels in STZ-induced diabetic mice. In KK-Ay mice 0.05% FA suppressed effectively blood glucose levels. In addition, FA inhibited the lipid peroxidation in brown adipose tissue of diabetic mice. Taken together, these findings suggest that dietary FA may be useful in alleviating oxidative stress and attenuating the hyperglycemic response associated with diabetes.