Background: Smooth and rapid induction, optimal operating conditions, and rapid recovery with minimal side effects such as nausea, vomiting, bleeding, and postoperative pain are the characteristics of ideal anesthetic. Objectives: To compare the effect of sub-arachnoid fentanyl and clonidine on onset & duration of sensory & motor block, post-operative pain relief, complications, side effects and hemodynamic status. Materials and Methods: This was a randomize controlled study conducted from July to November 2018. A total of 60 adult patients of American Society of Anaesthesiologists (ASA) physical status grade I or II, aged between 20-50 years, of either sex, posted for lower limb orthopedic surgery included after informed consent. All the patients were randomly allocated into one of the two groups using computer generated random number table. Group BF received induction with Fentanyl while group BC was induced Clonidine. Results: The baseline demographic analysis showed that the two groups did not differ significantly in age, weight, sex, ASA grade and operative times. Duration of motor, sensory & analgesia was higher in BC group. During the course of surgery, Heart Rate (HR) & Blood Pressure (BP) was significantly low in group BC at 15,30,40 & 45 minutes than in group BF and RR was also low in BF group at 30 minutes of post-operative period. Adverse effects and VAS score was low in BC group than BF group. Conclusion: Clonidine has significantly better hemodynamic stability, post-operative recovery and less post-operative complications compared to fentanyl.