Background: From our clinical experience, there were some problems in paratracheal stellate ganglion block at 6th cervical level (C 6 SGB), for example, lesser change in blood flow of the upper extremity and more occurrence of hoarseness. This study was undertaken to compare the various effectiveness of C 6 SGB and paratracheal stellate ganglion block at 7th cervical level (C 7 SGB). Methods: Forty patients were equally divided into 2 groups. In the Group I, patients were undertaken C 6 SGB with 0.25% bupivacaine 6 mL and in the Group II, patients were undertaken C 7 SGB with 0.25% bupivacaine 6mL. The skin temperature of index finger was measured before and after SGB and the warm sensation on face and upper extremity, hoarseness and upper extremity paralysis were studied. Results: The skin temperature of index finger was increased significantly from $33.95{pm}0.89^{circ}C$ to $34.51{pm}0.90^{circ}C$ in the Group I and from $33.94{pm}0.82^{circ}C$ to $35.38{pm}0.66^{circ}C$ in the Group II (P<0.05) The increase of skin temperature of index finger after procedure was $0.56{pm}0.09^{circ}C$ in the Group I and $1.44{pm}0.02^{circ}C$ in the Group II. The increase of skin temperature of index finger in the Group II was more statistically significant than Group I (P<0.05). The occurance of hoarseness in the Group II was significantly less than in the Group I. There was no significant difference in warm sensation on face and upper extremity and paralysis of upper extremity in both Groups. Conclusions: C 7 SGB showed better sympathetic block effect on upper extremity than C 6 SGB and hoarseness did not occur in C 7 SGB.