Background: Erector spinae plane block (ESPB) and Quadratus lumborum block (QLB) III are great interfacial plane blocks that have been providing a lot as regard perioperative pain relief in various surgeries. Objective: To compare the effect of both block on opioid consumption. Patients and methods: In a prospective randomized double blinded controlled trial, 102 (ASA 1 & II), aged 21- 64 y of both genders were scheduled to undergo open renal surgeries. They were separated into three groups at random (34 each). Control group where cases received general anesthesia alone, QLB group in which patients received unilateral QLB (III) before general anesthesia, with 20 ml of bupivacaine 0.25% and ESPB group in which patients received unilateral ESPB before general anesthesia, with 20 ml of bupivacaine 0.25%. Data collection included calculating amount of opioids given intra-operatively and 24h postoperatively, calculating time till end of block and evaluating patient satisfaction. Results: The current results demonstrated a non-significant recording in the two block groups as regard amount of analgesics given (intra-operative fentanyl being 125.15 ± 17.17 and 121.18 ± 16.1 in QLB and ESPB respectively), (postoperative morphine being11.09 ± 2.53 and 10.85 ± 2.34 in QLB and ESPB respectively), satisfaction score (being 5.71 ± 0.87 and 6.06 ± 0.69 in QLB and ESPB respectively), hemodynamics and VAS score recordings, while being significant when comparing the block groups to the non-block ones. Conclusion: ESPB and QLB provide relatively comparable analgesic effect with reduction of total intra-operative and post-operative opiate consumption in patients undergoing open renal surgery under general anesthesia.