Background and Objectives: Inguinal hernia repair done under peripheral nerve block provides many advantages compared to spinal or general anaesthesia. The aim of this study is to compare the functional outcome of Ultrasound guided ilioinguinal and iliohypogastric nerve block with spinal anaesthesia using 0.5% bupivacaine in terms of duration of post-operative analgesia, hemodynamic stability, time for ambulation, hospital stay and side effects. Methods: Forty adult patients aged 30 – 70 years with BMI 18 – 29.9 kg/m2 belonging to ASA physical status I & II undergoing elective open inguinal hernia repair were divided randomly into two groups of 20 to receive either Ultrasound guided ilioinguinal and iliohypogastric nerve block (Group U) using 0.5% bupivacaine 0.3 ml/kg or spinal anaesthesia (Group S) using 0.5% hyperbaric bupivacaine 3 ml (15 mg). Intra operative HR, SBP, DBP, MAP, SpO2 were recorded. Post-operatively patients were monitored for VAS score, ambulation time, time for first rescue analgesia, duration of hospital stay and side effects. Recorded data was compared between two groups using SPSS software. Qualitative data and quantitative data were compared using Chisquare test and independent‘t’ test respectively. A p value of less than 0.05 was taken as significant. Results and Discussion: The time for onset of sensory block was longer in Group U than for Group S. Mean VAS scores were less and duration of analgesia was longer in Group U than Group S. There was significant fall in SBP, DBP and MAP in Group S during the intraoperative period compared to Group U. The ambulation time and duration of hospital stay in Group S were much longer than Group U. Conclusion: Ultrasound guided Ilioinguinal & Iliohypogastric nerve block can be a safe alternative to spinal anaesthesia for elective unilateral inguinal hernia repair.