Background: Acute postoperative pain is a major problem, leads to undesirable outcome if not controlled probably. Therefore, appropriate management of acute perioperative pain using multimodal or balanced analgesia is crucial. The aim of the study was to compare between ultrasound guided quadratus lumborum block (QLB) and transversus abdominis plane (TAP) block as postoperative analgesia in lower abdominal surgeries. Patients & Methods: Thirty patients, aged from 21 to 50 years, ASA physical status I or II, scheduled for unilateral lower abdominal surgeries under general anesthesia were randomly divided into two equal groups of fifteen each. QLB group: patients received unilateral QLB block with 30 ml of 0.25% bupivacaine and TAP Group: Patients received unilateral TAP block with 30 ml of 0.25% bupivacaine. All patients in both groups were assessed for: Postoperative Visual analogue score (VAS), time to 1st rescue of analgesia, sensory block assessment (onset, level). In addition, total nalbuphine consumption in the first postoperative 24h and patient satisfaction were also recorded. Results: VAS was significantly higher in patients received TAP block. Patients received QLB showed rapid sensory loss with higher sensory block level in comparison to TAP block group. Time to 1st rescue of analgesia, was delayed in patients received QLB, so, this group showed longer duration of analgesia with higher satisfaction score than TAP group. In addition, the total nalbuphine consumption was higher in the first 24 hours in TAP block group compared to QLB group. Conclusion: The recently introduced QLB, may be a good option for postoperative pain relief after lower abdominal surgery with reduction of opioid consumption, prolonged duration of analgesia, and higher patient satisfaction compared to transversus abdominis plane block. We belief that if US guided QLB is performed by experienced hands; it is safe and effective technique for postoperative analgesia.