An improved method of inducing diabetes in dogs was developed. This method included 90% pancreatectomy, 2 mg/kg streptozotocin (STZ) perfused into pancreaticoduodenal artery, and the fixation suture of the duodenum to the costo-abdominal wall. Vasopressin injection administered to the animals before surgery reduced bleeding. All dogs used in this procedure survived and became diabetic. One month after the procedure the pancreatic islets were reduced in volume and the number compared with pancreas tissue obtained during the surgery. Acinar tissue remained with a normal histology, and exocrine function maintained the physiological parameters, except for a soft faecal consistency. We conclude that this procedure is effective in inducing experimental diabetes in dogs