OBJECTIVE: To compare the second and third cesarean section by clinical and statistical analysis. METHODS: From June 1993 to February 1997, we experienced 296 cases of the third cesarean section and 541 cases of the second cesarean section. We analyzed their incidence, age distribution, gestational week at operation, weight distribution of baby at birth, hemoglobin change, estimated blood loss during operation, obstetrical complication, combined operation, and degree of pelvic adhesion, presence of wound dehisence of uterus, post operative complication. RESULTS: Of the total deliveries, overall incidence of cesarean section was 51.4%, while the incidence of the second cesarean section was 16.0%, and that of the third cesarean section was 1.1%. In the third cesarean section the age group of 31-35 was most common(49.7%), and the most common gestational week at operation was 39th week(43.9%). In the third cesarean section, the hemoglobin change of 1.0g% less was most common(95.2%), and the most common amount of estimated blood loss was 400-600ml(61.0%). There was statistically significant difference of the blood transfusion rate between the third cesarean section(41 cases, 13.8%, p=0.04) and second cesarean section(27 cases, 5.0%). The most common combined operation in the third cesarean section was tubal ligation(51.7%), and the others were bladder wall repair(2.0%), cesarean hysterectomy(1.7%). In the third cesarean section, the incidence of mild intraabdominal adhesion was 16. 9% and that of severe adhesion was 11.8%. It was statistically significant compared to the second cesarean section. Among the complications of the third cesarean section, there were 9 cases of placenta accreta(3.0%), 4 cases of placenta previa totalis(1.4%), and 1 case of uterine rupture, uterine atony, uterine arterial rupture(0.3% each other), and did not proved statistical significance. CONCLUSION: In this study, we found that the rate of blood transfusion, cesarean hysterectomy, bladder wall repair, and the degree of intraabdominal adhesion were more common in the third cesarean section than second section. But, if pre- & postoperative management is adequate, maternal mobidity and neonatal mobidity is not affected.