Background: Patients who undergo midline incision colorectal surgery often experience moderate to severe postoperative pain, which lead to high level of opioid need. Transversus Abdominis Plane (TAP) block is a component of multimodal analgesia which May reduce postoperative pain and amount of opioid consumption. This study aims to compare the effectiveness of Linea Semilunaris approaches to Lateral approach of TAP block on the postoperative pain, duration of the postoperative analgesia effect and quality of postoperative recovery in patients undergoing colorectal surgery with general anesthesia Methods: This study was a single blind random controlled trial. Forty patients who met the criteria and were planned for colorectal surgery under general anesthesia at Prof. Dr. IGNG Ngoerah General Hospital, Denpasar. Subjects were then randomly allocated into 2 groups, group P1 were planned to receive bilateral TAP block with semilunar approach, while group P2 were planned to receive bilateral TAP block with lateral approach. Both treatment groups received Bupivacaine 0.25% 20 ml on each side of the abdomen postoperatively. Furthermore, an evaluation of pain intensity (VAS) was carried out at 1, 6, 12, 24 and 48 hours postoperatively, recording the duration of the analgesic and the quality of postoperative recovery which was assessed using the QoR-40 questionnaire. Results: There were no significant differences in demographic characteristics between the two groups. Statistical tests showed that group P1 had lower pain intensity (VASE) at 6 hours (median: 0 vs. 3), 12 (mean: 2.42 vs. 3.36), and 24 (mean:2.45 vs. 3.18) (p < 0.001), longer duration of analgesic effect (minutes) (median:460 vs. 260, p < 0.001), lower total opioid morphine requirement (mg) in 24 hours (median 3 vs. 5, p < 0.001) and higher quality of recovery (QoR-40 score) of patients at 24 hours (median 180 vs. 147.5, p < 0.001) and 48 hours (median: 181.5 vs. 151.5, p < 0.001). Conclusion: Bilateral TAP block in with semilunar approach show better analgesia effectiveness and quality of recovery after midline incision colorectal surgery than lateral approach