Objective: To evaluate and compare the efficacy, duration of post-operative analgesia and untoward effects of intrathecal Clonidine 60__ampersandsignmu;g and intrathecal Buprenorphine 60__ampersandsignmu;g used as additive adjuvants in spinal anesthesia for lower limb orthopaedic surgeries. Method: Total 80 patients, aged 20-60 yrs, belonging to ASA grade I and II undergoing elective or emergency lower limb orthopaedic surgery scheduled to last less than 180 minutes and fit to receive spinal analgesia were randomly allocated into two groups. Group C received intrathecal 0.5% heavy Bupivacaine 3.0 ml with Clonidine 60__ampersandsignmu;g and Group B received intrathecal 0.5%. Heavy Bupivacaine 3.0 ml with Buprenorphine 60__ampersandsignmu;g. Duration of subarachnoid block, total analgesia, effective analgesia, number of rescue analgesics and any untoward effects were assessed and compared in both groups. Results: Both groups were comparable in demographic data. The difference in the duration of subarachnoid block in both groups is statistically significant. The duration of total analgesia in both groups is statistically comparable. Effective analgesia in Clonidine group was statistically longer than Buprenorphine group. The nausea was noted in 17.5% of patients in Buprenorphine group and 7.5% patients in Clonidine group. Vomiting was present in 5% of patients in Buprenorphine group while none of the patient in Clonidine group had vomiting. Conclusion: This study concludes that intrathecal Clonidine 60__ampersandsignmu;g significantly prolongs the duration of spinal anesthesia and quality of analgesia was acceptable to patients in both groups though VAS assessment was better in Buprenorphine group. Hence we suggest that combination of low dose intrathecal __ampersandsignalpha;2 agonist and opioid would give better analgesia __ampersandsignamp; might reduce incidence of untoward effects.