Objective The aim of this study was to evaluate intraperitoneal (IP) lidocaine administration and intravenous (IV) lidocaine infusion for postoperative pain control after cesarean section. Study design This is a prospective randomized, double-blind, placebo-controlled study. Patients and methods A total of 165 pregnant full-term women who were indicated for elective cesarean delivery for various indications were randomized equally to either group C (control, IP and IV saline), group IP (IP lidocaine administration), or group IV (IV lidocaine infusion). Five patients were excluded from each group for various reasons. The outcome measures were postoperative pain scoring, total pethidine consumption, and the need for postoperative analgesia. Results There was significantly reduced visual analogue scale scores after 4 h, total pethidine consumption in 24 h, time to ambulation, onset of pain relief, and the need for rescue analgesia in groups IV and IP compared with controls. Postoperative nausea and vomiting were less frequently noted in groups IP and IV than in group C, but this trend was not statistically significant. Conclusion The IP lidocaine instillation and IV lidocaine infusion significantly reduced postoperative pain and opioid consumption in women who underwent elective cesarean section, compared with control infusions.