Aim: The aim of the present study was comparing the duration of analgesia in terms of the time of the first analgesic requirement of intrathecal levobupivacaine combined with nalbuphine and fentanyl for lower abdominal surgeries.Methods: This randomized double-blinded study was conducted on 100 patients from November 1, 2023 to Nov 5, 2024 at Department of Anesthesiology, Madha Medical College and Hospital, Kovur Chennai. The study received Institutional Ethical Committee approval before its initiation.Results: There were 26 patients in the age group of <30 years in group A and 24 patients who underwent surgery in group B. 10 patients were in the age group of 31-40 years in each group from the study participants. Most study participants were females in both groups, with 28 female patients in group A and 32 female patients in group B. 5 and 6 patients were below 50 kgs weight in groups A and B, respectively. 60-90 mins of surgery were performed among 24 group A participants and 10 participants in group B. The surgery duration for 14 and 124 patients was 91- 120 minutes in groups A and B, respectively. The maximum sensory loss was found in T6, T7, T8, and T9 dermatomes in both groups. A smaller number of patients encountered sensory loss in T4 and T5 dermatomes. The mean and SD for the onset of sensory function were 6.03±1.21 and 6.20±1.10 in groups A and B, respectively. The mean and SD values for the onset of motor function after anaesthesia were 13.32±1.06 in group A and 13.28±1.06 in group B. time for maximum sensory loss was 13.40±1.11 and 13.22±1.03 in groups A and B, respectively.Conclusion: We concluded that intrathecal nalbuphine combined with levobupivacaine is comparatively better than intrathecal fentanyl combined with levobupivacaine in terms of postoperative pain relief. Thus, doses of analgesics required during the postoperative period were less, with no difference in hemodynamic parameters like pulse rate, systolic and diastolic blood pressure, and oxygen saturation.