Background: An effective interfascial plane block for laparoscopic (lap) cholecystectomy and other abdominal procedures is the Quadratus Lumborum Block type II (QLB-II). The erector spinae plane block (ESPB), which is guided by ultrasound (US), is a recently described interfascial plane block that is gaining popularity. This research aims to evaluate the relative effectiveness of ultrasound ESPB and US QLB in the treatment of immediate post-operation pain following lap cholecystectomy. Methods: Sixty cases (21-65 years old, from both sexes) having elective lap cholecystectomy were enrolled in this prospective randomized double-blind research. The cases were randomly classified into three equal groups, C group: received general anesthesia (GA) only, ESPB: received GA and bilateral US ESPB and QLB: received GA and bilateral US QLB. Results: Duration of performing block was significantly less in group ESPB versus group QLB. Intraoperative heart rate and mean arterial pressure were significantly less after incising the skin, at 30 min in ESPB and QLBs versus group C. Total fentanyl dosage and morphine dosage in 1 st 1 day were significantly less in group ESPB and QLB versus group C. NRS at 6, 24 hour was significantly less in ESPB and QLBs versus group C. First time to call for analgesic requirement was significantly delayed in the ESPB and QLBs versus the C group. Conclusions:The ESPB is as efficient as posterior QLB to provide effective analgesia as comparable results of lower NRS, intraoperative fentanyl and post-operation opioid dosage, delayed first time to call for analgesic requirement and is lower side effects versus control in cases undergoing elective laparoscopic cholecystectomy.