Introduction: Adjuncts to local anesthetics for brachial plexus blockmay enhance the quality and duration of analgesia. Buprenorphine and Fentanyl both are opioids, known to produce antinociception and enhance the effect of local anesthetics. The purpose of this study was to compare the effect of Buprenorphine and Fentanyl added to brachial plexus block by supraclavicular approach.