In six patients with primary Sjögren's syndrome defined with HLA-antigens and no clinical signs of pancreatitis, the pancreatic ductal morphology (as described by endoscopic retrograde pancreatography), serum pancreatic enzymes, and fecal fat excretion were examined and secretin test was carried out. Further, oral glucose tolerance test with concomitant determination of serum insulin and C-peptide were done. All patients had at least two pathological signs of exocrine function and/or ductal morphology. There was no evidence of endocrine malfunction. The findings are suggestive of the existence of a clinically silent pancreatitis, perhaps of autoimmune etiology.