Background: Brachial plexus block has now evolved into a valuable and safe alternative to general anaesthesia for upper limb surgeries. Various approaches like interscalene, supraclavicular, infraclavicular and axillary have been used for blocking the brachial plexus. Supraclavicular approach gives the most effective block for upper extremity and is carried out at level of trunks of brachial plexus. Objectives: To determine and compare the efficacy of supraclavicular block of brachial plexus with bupivacaine (0.5%) with dexmedetomidine (30 µg) and levobupivacaine (0.5%) with dexmedetomidine (30 µg) for brachial plexus blockade. Material & Method: This prospective, randomized, double blinded, controlled trial was conducted on patients of either sex, aged between 18 to 60 years with ASA class I and II posted for upper limb surgeries. Two groups comprising of 30 patient in each group, who received bupivacaine + dexmedetomidine, or levobupivacaine + dexmedetomidine, were selected to compare their effects on onset, duration and quality of BPB. Results: Onset of sensory block was early in Group B (6.45+0.91 minutes) as compared to that in Group A (8.02+0.82 minutes). Onset of motor block too was early in Group B (9.02+0.90 min) as compared to Group A (10.01+0.88 min.) Duration of sensory block was statistically significantly longer in Group B (891.50+68.38 min) as compared to Group A (756.67+64.68 min). Duration of motor block was statistically significantly longer in Group B (788.83+62.97 min) as compared to Group A (700.67+64.67 min). Duration of total block was statistically significantly longer in Group B (1002.67+43.54 min) as compared to Group A (787.07+61.62 min). Conclusion: Our study revealed that 30μg dexmedetomidine as adjuvant to levobupivacaine in supraclavicular brachial plexus block improves sensory, motor block characteristics, hemodynamics, and VAS pain scores without clinically relevant adverse effects.