A transient depression of blood-glucose level was found after streptozotocin administration, which can be explained by insulin release due to the destroying effect of streptozotocin on beta-cells of pancreas, the biliary flow was elevated, when blood sugar level was low. After the transient decrease the blood glucose level was elevated and remained in a diabetic range (300-500 mg/100 ml). During the diabetic period a biphasic change was observed in the biliary flow: 23-48 hours after streptozotocin injection a depression, however, 5-10 days after streptozotocin administration an elevation was detected in the bile flow. Changes found in biliary excretion rate of exogenous organic anions were parallel with those of biliary flow.