Introduction Recently, regional anesthesia techniques have been replaced by peripheral nerve blocks in the management of perioperative pain. Because of the widespread use of ultrasonography, it has been reported that peripheral nerve blocks showed similar analgesic efficacy with favorable rates of side effects when compared to central blocks. Central nerve blocks are often used in combination with general anesthesia for pediatric surgery in order to reduce general anesthetic requirements, opioid use, postoperative pain, nausea and vomiting, and risk of anesthetic neurotoxicity, particularly in young patients [1-4]. Caudal epidural block (CEB) is a well-established and commonly performed neuraxial technique for providing intraoperative and postoperative analgesia in pediatric patients scheduled for lower abdominal perineal surgical interventions [5-6]. Although the efficacy and safety of CEB are fairly high [7], the associated complications such as inadvertent dural puncture, unwarranted motor blockade of lower limbs, and disturbance of bladder function [8] might limit its use. Undoubtedly, introduction of ultrasonography into anesthesia practice has led to an increase in practice of peripheral nerve blocks. Ultrasonography guidance has significantly facilitated the practice of regional nerve blockades [9]. There has been a growing interest in ultrasound-guided transversus abdominis plane (TAP) block as an alternative and valid postoperative analgesic method in pediatric patients undergoing lower abdominal surgery [10]. Quadratus lumborum block (QL block) is a new abdominal and truncal block used for providing somatic Background/aim: Despite different regional anesthesia techniques used to provide intraoperative and postoperative analgesia in pediatric patients, the analgesic effectiveness of peripheral nerve blockades with minimal side effect profiles have not yet been fully determined. We aimed to compare the efficacy of ultrasound-guided transversus abdominis plane (TAP) block, quadratus lumborum (QL) block, and caudal epidural block on perioperative analgesia in pediatric patients aged between 6 months and 14 years who underwent elective unilateral lower abdominal wall surgery. Materials and methods: Ninety-four patients classified under the American Society of Anesthesiologists physical status classification system as ASA I or ASA II were randomly divided into 3 equal groups to perform TAP, QL or Caudal epidural block using 0.25% of bupivacaine solution (0.5 ml kg −1). Results: Postoperative analgesic consumption was highest in the TAP block group (P < 0.05). In the QL block group, Pediatric Objective Pain Scale (POAS) scores were statistically significantly lower after 2 and 4 h (P < 0.05). The length of hospital stay was significantly longer in the caudal block group than the QL block group (P < 0.05). Conclusion: We suggest that analgesia with ultrasound-guided QL block should be considered as an option for perioperative analgesia in pediatric patients undergoing lower abdominal surgery if the expertise an...