INTRODUCTION We present a study in which fifty patients between 30–60 years, undergoing laparoscopic cholecystectomy for cholelithiasis under general anaesthesia were included. Bilateral Quadratus lumborum (QL) block using local anaesthetic levobupivacaine was given in study group (n=25) and Inj. diclofenac intramuscular (75mg) was given in control group (n=25). Postoperative analgesia of study group was compared with control group using fentanyl via patient controlled analgesia pump over 24hrs. MATERIAL AND METHODS After completion of surgery, ultrasound guided QL block was performed on both sides using posterior approach. OBSERVATIONS AND RESULT When compared between the two groups the mean total fentanyl consumption and the time of demand of first rescue analgesic dose there was clinically and statistically significant difference (p ˂ 0.001). CONCLUSION Bilateral QL block via posterior approach is effective in providing post operative pain relief over 24 hrs period after laparoscopic cholecystectomy.