Background: Relief of pain during surgery and in postoperative period is an aspect in surgical patients to make surgery uneventful. Few studies have observed that premixing adjuvants with local anaesthetic can alter the spread of the drug in the CSF. Hence administering adjuvants in separate syringes may reduce the change in density of both the drugs, which will prevent alteration in CSF spread. Hence the aim of this study is to evaluate the efficacy of intrathecal hyperbaric Bupivacaine with Buprenorphine premixed and sequentially to compare post-operative analgesia and rescue analgesia required over 24 hrs. Methods: This is a prospective, randomized single blind study involving 100 patients posted for elective total abdominal hysterectomy surgeries under spinal anaesthesia with ASA I and II, not known allergy to local anaesthetic, no infection at the site of injection. VAS score and vital parameters such as HR, NIBP, and SP02 were recorded in intra-operative and post-operative period. Blockade characteristics were recorded intra-operatively. Results: Mean heart rate, MAP, along with duration of time of onset of sensory block, motor block, Time for maximal blockade and regression time to T10 between two groups was compared and the difference was statistically significant. In the both groups VAS values were statistically significant at 4 hours, 6 hours, and 12 hours; however, group S had better postoperative pain relief than group M. Conclusion: We observed that sequential administration of buprenorphine with hyperbaric bupivacaine results in earlier onset of action, prolonged duration of sensory and motor blockade, prolonged duration of postoperative analgesia and less number of rescue analgesia when compared with administration of premixed buprenorphine with hyperbaric bupivacaine.