Background :Cesarean section delivery is becoming more frequent. Childbirth is anemotion-filled event and the mother needs to bond with her newbornbaby as early as possible. Any intervention that leads to improvement inpain relief is worthy of investigation. Large amounts of opioid analgesicdrugs are often required in the management of intense post operativepain. However this option is associated with many side effects, includingevident disruption of mother/newborn bonding. Local anesthetics, eitheron their own or in combination with opioids or nonsteroidal antiinflammatorydrugs, have been employed as an adjunct to otherpostoperative pain relief strategies.Methodology:100 healthy pregnant full term female going to have elective cesareansection, after explanation of its aim and details and after obtaining awritten consent.All patients had cesarean section under spinal anesthesia and receivedpost-operative analgesia [pethidine] according to visual analogue scalevalue. Pain was assessed 15 minutes after skin closure using a 100 pointvisual analogue scale (VAS) which was continued in the ward at 1, 2,4,8,16 and 24 hours postoperatively.The amount of pethidine consumed after 1, 2, 4, 8, 16 and 24 hours wascalculated.They have been randomized into 3 groups 1-The 1st group C (n=50 women):Patient had Routine cesarean section.Patient only receive pethidine post-operative according to visual analoguescale.2-The 2nd group B (n=25 women):Patient had Routine cesarean section.The wound was infiltrated during closure, with 30 ml of 0.5 %bupivacaine.Patient received pethidine post-operative according to visual analoguescale.3-The 3rd group B+M (n=25 women)Patient had Routine cesarean section.The wound was infiltrated during closure with 30 ml of 0.5 %bupivacaine plus 750 mg MgSO4.Patient received pethidine post-operative according to visual analoguescale.Blood sample collected before surgery and after surgery by 2hours andlevel of magnesium in blood was calculated.Results:There was a statistically significant differences between group B using0.5% Bupivacaine compared to control group as regard the totalconsumption of pethedine in 24 hour and lactation in first 12 hour.Therewas a statistically significant differences between group B+M using0.5% Bupivacaine plus magnesium sulphate compared to control group asregard the total consumption of pethedine in 24 hour and lactation in first 12 hour. There was no significant difference between group B using0.5% Bupivacaine and group B+M using 0.5% Bupivacaine plusmagnesium sulphate , as regard the total consumption of pethedine in 24hour or lactation in first 12hour.Conclusion:We concluded that infiltration of the surgical wound of a cesarean sectionwith 0.5 % bupivacaine with or without the addition of magnesiumsulphate after spinal anesthesia provided a significant degree of analgesiaas shown by the smaller pain scores and pethidine consumption andearlier onset of lactation.