Introduction: Supraclavicular approach to brachial plexus block produces the most complete upper limb block as it blocks the brachial plexus at the level of the trunks formed by C5-T1 nerve roots.Ropivacaine is a pure S enantiomer with greater differentiation between sensory and motor block with better margin of safety due to reduced toxic potential. The aim of this study was to compare sensory and motor block effectiveness of 0.5% ropivacaine to that of 0.5% bupivacaine for supraclavicular brachial plexus block in upper limb surgeries. Materials and Method: In this prospective randomized study total 60 patients undergoing upper extremity surgeries were given block using a peripheral nerve stimulator. Group A received 0.5% ropivacaine, 30ml and Group B received 0.5% bupivacaine, 30ml. Sucess of the block was assessed by determining loss of shoulder abduction and loss of pinprick in the C5- T1 dermatomes. The onset of action (sensory and motor) and duration of action (sensory, motor) were recorded. Post operative analgesia was assessed by using visual analog scale. The results were tabulated and statistically analyzed. Results: There was statistically significant difference in the mean onset time to achieve maximum sensory level between group A(7.87+/-2.13mins) and group B(9.53+/-2.45mins). Duration of sensory block and analgesia was similar in both the groups. However motor block was more prolonged in group B(556+/-93.7mins) as compared to, group A(467+/-92.5 mins). Conclusion: Ropivacaine is a suitable alternative to bupivacaine in supraclavicular brachial plexus block for upper limb surgeries.