BACKGROUND: Stellate ganglion block (SGB) has been used to treat over 150 diseases which include diabetes mellitus and gout. This study was planned to investigate whether stellate ganglion block (SGB) could lower the levels of blood glucose, uric acid, epinephrine, and norepinephrine. METHODS: Sixty Sprague-Dawley rats within the weight of 250-350 gm were randomly devided into four groups. CS group was normal group with sham SGB with normal saline, CL group was normal group with SGB with lidocaine, DS group was diabetic group with SGB with normal saline, DL group was diabetic group with SGB with lidocaine. The diabetes was induced by intraperitoneal injection of 40 mg/kg of streptozotocin in citrate buffer (0.01 M, pH 4.5). Nondiabetic groups were given same amount of the citrate buffer. Seven days after the last injection of the streptozotocin blood glucose level was checked and more than 300 mg/dl was considered diabetic. The SGB was performed three times at right superior cervical ganglion two days apart from two days after the conformation of diabetes. Successful SGB was conformed by the ipsilateral ptosis or conjunctival congestion. Blood samplings from tail vein for the check of glucose, uric acid, and catecholamines were done before the injection of streptozotocin, seven days after the last injection of streptozotocin, and two days after the last SGB. RESULTS: The SGB with lidocaine reduced the blood glucose level only in the diabetic rats while SGB with the saline did not. The epinephrine levels were increased in the diabetics and decreased by the SGB with lidocaine without any statistical significance. Norepinephrine and uric acid levels had not been effected by the SGB and both of them had no correlationship with the glucose level. CONCLUSIONS: SGB in the diabetic rats decreases the blood glucose level. But for the effects of the SGB on the level of epinephrine further study would be needed.