Objectives: Inguinal hernia repair is one of the most common daily surgeries performed in pediatrics. This prospective randomized clinical trial aims to compare ultrasound (USG)-guided ilioinguinal/iliohypogastric (IL/IH) nerve block and pre-incisional wound infiltration (PWI) in terms of post-operative analgesia on pediatric unilateral inguinal hernia repair. Methods: After receiving ethics committee approval, 65 children aged 1–6 years who had unilateral inguinal hernia repair were allocated to USG-guided IL/IH nerve block (group IL/IH, n=32) and (group PWI, n=33). In both groups, 0.5 mg/kg 0.25% bupivacaine+2% prilocaine mixture was used by calculating the volume as 0.5 mL/kg for the block and infiltration. The primary outcome was to compare both groups’ post-operative Face, Legs, Activity, Cry and Consolability (FLACC) scores. The secondary outcomes included the time to first analgesic request and the total acetaminophen consumption. Results: The FLACC pain scores at the 1st, 3rd, 6th, and 12th h were statistically significantly lower in group IL/IH than in group PWI (p=0.013, p<0.001, p<0.001, and p=0.037, respectively) (p<0.001). There was no difference between the groups at the 10th and 30th min and at 24 h (p=0.472, p=0.586, and p=0.419, respectively) (p>0.05). Conclusion: USG-guided IL/IH nerve block in pediatric patients with inguinal hernia repair was found to be superior to PWI in terms of lower pain scores, less additional analgesia requirement, and longer first analgesia requirement.