The rapid i.v. injection of 60 mg streptozotocin/kg body weight 8 days after an initial dose of 30 mg/kg was the best method to produce a distinct insulin-deficient diabetes in minipigs. Even in the absence of any therapy the further course of this diabetes remained stable without tending to exhibit ketoacidosis. Besides hyperglycaemia and the loss of insulin response to glucose there was significant increase of triglycerides and a decrease of plasma albumin. In the oldest animals this diabetes has so far been observed for more than 3 years. Because of some special advantages this experimental diabetes could provide a useful model for studying diabetic angiopathies.