COCHRAN ET AL 1 in 1956 described a clinical condition characterized by hypoglycemic convulsions which were aggravated by a high protein diet. They noted that the leucine in the diet of these patients precipitated the episodes of hypoglycemia, whereas this did not occur when leucine was administered to unaffected individuals. A convulsive disorder was noted in the parents of some of these patients as well as a sensitivity to leucine. 2 The outlook for normal mental development was considered poor. Despite numerous studies of this disorder, it remains a poorly defined entity, and Greenberg and Reaven 3 have recently questioned the clinical value of classifying patients with hypoglycemia according to their response to leucine. This report presents two cases of leucine-induced hypoglycemia. Both patients have apparently had correction of a convulsive disorder by the institution of a low leucine diet with postprandial carbohydrate supplementation. Both appear to be mentally normal.