Abstract. Hormonal responses (glucagon, pancreatic polypeptide and somatostatin) to iv glucagon, iv arginine, and ingestion of a mixed meal were investigated in 6 patients with insulin-dependent diabetes secondary to chronic pancreatitis without beta-cell function, in 8 Type I (insulin-dependent) diabetics without beta-cell function, and 8 healthy subjects. No significant differences were found between the two diabetic groups regarding glucagon responses to arginine and meal ingestion. In the patients with diabetes secondary to chronic pancreatitis compared with Type I diabetics and normal controls, the pancreatic polypeptide concentrations were significantly lower and somatostatin concentrations were significantly higher after glucagon, arginine and a mixed meal. Thus, pancreatic glucagon secretion was preserved in patients with insulin-dependent diabetes secondary to chronic pancreatitis, having no residual beta-cell function. These findings suggest that pancreatic glucagon deficiency is not absolute in insulin-dependent diabetes secondary to chronic pancreatitis. A high level of somatostatin may contribute to a lower blood glucose level in patients with chronic pancreatitis.