Context: The assessment of the efficacy of low dose (30 micrograms) of dexmeditomedine added to 0.25% bupivacaine was studied for the prolongation of the duration of sensory and motor block in supraclavicular brachial plexus block was the aim of our study. Methods: This was a prospective double blind randomized study conducted on sixty patients posted for upper limb surgeries between the age group of 18 to 60 years, the patients were randomly allocated to two groups of 30 each. The control group (C) received 37 ml of 0.25% bupivacaine with 3 ml of normal saline; while the study group (S) received 37 ml of 0.25% bupivacaine with 3 ml of normal saline containing 30 micrograms of dexmeditomedine. Assesment of sensory and motor block was done with the monitoring of heart rate, blood pressure and peripheral oxygen saturation throughout the procedure and postoperatively till the waning of block effect. The duration of analgesia and occurance of various side effects was noted. Results: It was observed that the onset time for sensory and motor block was similar in both the groups. The duration of sensory and motor block and post operative analgesia was longer in the study group and was statistically significant. Adverse effects like bradycardia, hypotension, nausea and vomiting were insignificant occurred in one or two cases. Conclusion: Dexmeditomedine in the doses of 30 µg added to bupivacaine as an adjuvant prolongs the duration of sensory and motor block with no significant side effects.