Background: Various adjuvants to local anaesthetics are added to improve the quality of subarachnoid block in unilateral anaesthesia during lower limb surgeries. The present study was conducted with the aim to evaluate the efficacy of combination of clonidine-bupivacaine and fentanyl-bupivacaine.Methods: This randomized study was conducted on 60 patients at tertiary care center (Topiwala National Medical College, Mumbai) for 2 years. They were divided into 2 groups consisting of 30 in each. Group BC receives Inj. bupivacaine 0.5% (hyperbaric) 7.5 mg (1.5 ml) with inj. clonidine 15 µg (0.1 ml) intrathecally and Group BF receives Inj. bupivacaine 0.5% (hyperbaric) 7.5 mg (1.5 ml) with inj. fentanyl 15 µg (0.3 ml) intrathecally. The time of onset and duration and level of sensory and motor block, time to complete sensory and motor block recovery and duration of spinal anaesthesia, intraoperative and postoperative hemodynamics and side effects if any were noted.Results: The time of onset and duration of sensory and motor block was lesser in group BF compared to BC but the difference was statistically not significant (p>0.05). Duration of analgesia was also higher in group BF. Intraoperative and postoperative changes in hemodynamic parameters, oxygen saturation, and respiratory rate were comparable, and no significant changes are observed, and all are with in normal range (p<0.05). Pruritus was noticed in group BF (10%). None of the patient in both groups show any side effects such as respiratory depression and nausea, vomiting.Conclusions: We conclude that addition of fentanyl and clonidine to hyperbaric bupivacaine produces almost similar effect in unilateral spinal anaesthesia for lower limb surgery without prolonged motor blockade, haemodynamic instability, respiratory depression and nausea and vomiting with good sedation and postoperative analgesia. Although the incidence of pruritus is more with fentanyl, it is not distressing for patients.