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Background and Aims Quadratus lumborum block (QLB) and intrathecal morphine are commonly used in multimodal analgesia to manage postoperative pain following cesarean section. This prospective, randomized, controlled, and single-blinded study aimed to compare the analgesic effects of anterior QLB and intrathecal morphine in patients undergoing cesarean delivery under spinal anesthesia.Methods Patients scheduled for cesarean delivery under spinal anesthesia were randomized into three groups: Group Q (bilateral anterior QLB), Group M (100 µg intrathecal morphine), and Group C (standard spinal anesthesia). The primary outcome was total diclofenac consumption within 24 hours. Secondary outcomes included NRS scores, time to first rescue analgesia, and side effectsResults There was no significant difference in total diclofenac consumption during the first 24 hours among the three groups. However, post-hoc analysis showed that patients in the QLB group required significantly less analgesic than those in the control group (p=0.027). At the 8th postoperative hour, pain scores were also lower in both the QLB and morphine groups compared to the control group. In the post hoc analyses, both iNRS and dNRS scores at the 4th postoperative hour were significantly lower in Group M compared to Group C (p = 0.030 and p = 0.029, respectively). The time to first rescue analgesia did not differ significantly between groups. Side effects such as pruritus, nausea, and vomiting were reported more frequently in the morphine group.Conclusions Both anterior quadratus lumborum block and intrathecal morphine provided effective postoperative analgesia following cesarean delivery compared to control. While pain scores and time to first rescue analgesia favored the intervention groups, only QLB significantly reduced diclofenac consumption. Moreover, QLB was associated with fewer opioid-related adverse effects, suggesting it may be a safer alternative to intrathecal morphine within multimodal analgesia protocols.