Background: The popularity of supraclavicular brachial plexus block in upper limb surgery in recent years are due to better understanding of using adjuvant to local anaesthetics, its advantages and in avoidance of the hazards of general anaesthesia. Aim: To compare anaesthetic and analgesic properties of clonidine or fentanyl as an adjuvant to bupivacaine in supraclavicular brachial plexus block in upper limb surgeries. Method: A total number of 90 patients (ASA class 1 and II) were selected randomly into three groups, thirty in each group. Group–A (control group) received bupivacaine (0.25%) 28ml and 2ml 0.9% Ns, total of 30ml. Group–B (study group) received fentanyl (100μg) 2ml and bupivacaine (0.25%) 28ml, total of 30ml. Group–C (study group) received clonidine (150μg) 2ml and bupivacaine (0.25%) 28ml, total of 30ml.The parameters including pulse rate, non invasive systolic and diastolic blood pressure, respiratory rate, SpO2, onset and duration of motor and sensory block, postoperative pain score in VAS, duration of analgesia, first analgesic demand, side effects were assessed and recorded. Result: The difference in onset of sensory & motor block (early in clonidine group), duration of sensory & motor block and duration of analgesia (prolonged in clonidine group) was found to be statistically significant between all the groups (p<0.05). But intensity of pain measured by VAS in group A was highest at 18 hrs group–B and group–C expressed highest at 24 hours of postoperative period with group C showing lower VAS. Duration of analgesia (time from supraclavicular block to first analgesic demand) in study group–C had significantly longer mean duration than that produced by Group B and control group–A (18.2 ± 2.5 vs 15.4 ± 1.2 and 8.2 ± 1.3 hours P<0.001). Conclusion: Clonidine and bupivacaine combination is a better alternative to fentanyl and bupivacaine in respect of quality of anaesthesia and duration of analgesia.