Aim: This study was designed to evaluate analgesic efficacy, duration of sensory and motor block, hemodynamic stability and adverse effects of intrathecal morphine and intrathecal dexmedetomidine as an adjuvant to bupivacaine in spinal anesthesia in patients undergoing lower abdominal surgeries. Methods: This was a prospective, randomized, double-blind study involving 30 patients in each group. Group A received 15 mg of 0.5% hyperbaric bupivacaine with 250 μg of morphine while Group B received 15 mg of 0.5% hyperbaric bupivacaine with 5 μg of dexmedetomidine. Sensory and motor characteristics of spinal block, time for first rescue analgesia, the total dose of rescue analgesia required and side effects were noted perioperatively. Results: The duration of sensory and motor blockade was significantly longer in dexmedetomidine group than in morphine group. Time for first rescue analgesia and total analgesic dose were similar in both groups. The itching was noticed only in morphine group, nausea and vomiting occurred in both groups and there was no respiratory depression occurred in the two groups. Conclusion: Intrathecal dexmedetomidine produces prolongation of sensory and motor blockade with less undesirable side effects than morphine