Introduction: Upper limb surgeries can be done under general anesthesia. However, using Brachial plexus block is a better alternative. This method provides good muscular relaxation and also maintains intraoperative hemodynamics at a stable level. Aim of the study: To study the effect of Midazolam added to brachial plexus block by supraclavicular approach. Materials and methods: This was a prospective, randomized, single blinded study. A total of 100ASA Grade I or II adult patients who underwent upper limb surgeries under supraclavicular brachial plexus block were studied. Patients were randomly allocated to two groups of 50 each. Patients in Group B received 30 mL of 0.375% Bupivacaine and Group BM received 30 mL of 0.375% Bupivacaine with preservative free Midazolam 0.05 mg/kg. The onset time and duration of sensory and motor blockade were noted. The patients were observed for 24 hours postoperatively for hemodynamic variables, sedation scores and rescue analgesic requirements. Results: Group BM showed significantly quicker onset of sensory and motor block than Group B (p < 0.05). Group BM also had significantly longer duration of sensory and motor block (p < 0.05). Group BM had significantly less requirements for rescue analgesia (p < 0.05). Both groups showed similar hemodynamics and sedation scores postoperatively. Conclusion: Midazolam (0.05 mg/kg) in combination with 30 mL of Bupivacaine (0.375%) hastened onset of sensory and motor block, and improved postoperative analgesia when used in brachial plexus block, without producing any adverse events.