Background: Postoperative pain relief after caesarean section (CS) requires the balance between pain relief and side effects of the drug used or the procedure. Objective: To assess the role of post- operative analgesia using rectal diclofenac; and intra-muscular (I/M) pethidine; and their side effects in women delivered by cesarean section at Omdurman Maternity Hospital (OMH) 2017. Methods: This is a prospective cross-sectional hospital-based study conducted during the first six months of 2017. Women delivered by uneventful CS under spinalanaethesia (SA) were included in the study after an informed consent. Unless contra-indicated; all women received a non-steroidal anti-inflammatory drug (NSAID); diclofenac sodium 75 mg, given rectally immediately after operation and repeated every eight hours during the first 24 hours or when needed. Women with contraindication for NSAID or when pain was persistent in spite of repeated NSAID; were given an opioid; pethidine or tramadol 100 mg intramuscularly (I/M). Women were assessed for blood pressure, pulse, respiratory rate and symptoms of pain, headache, post partum haemorrhage (PPH), nausea and vomiting. Data was collected by trained data collectors using a structured format. Results: A total of 15209 delivered in this hospital during six months, 9974 (65.6%) delivered vaginally and 5235 (34.4%) by CS. Elective CS were 2947 (56.3%) and emergency CS were 2288 (43.7%). Out of those delivered by CS, 4800 (91.7%) received diclofenac (vortex) and 435 (8.3%) received pethidine. There was no significant difference between the two groups in their socio- demographic characteristics or their pulse rate, blood pressure and respiratory rate (PV = 0.150). Nausea and vomiting were mild in both groups, whereas in diclofenac are less than pethidine (PV= 0.05), other side effects were not reported in either of the two groups. Patient’ satisfaction and hospital stay were almost the same in both groups. Conclusion: Postoperative Use of diclofenachas provided good analgesic effect, greaterpatient satisfaction, reduced consumption of opioids, less side effects and shorter hospital stay for women underwent cesarean section.