Endometriosis is a gynecologic disease. The prevalence of endometriosis in the reproductive age of women varies between 3-10%. Cesarean scar endometriosis is a rare event and rare cases have been reported in gynecologic and surgical articles. The incidence of cesarean section scar endometriosis is not accurately determined but ranges from 0.03% to 0.15% and in some other articles the incidence up to 1% has been reported. Frequently the cesarean scar endometriosis is not diagnosed until before surgery (80%) and usually the patients are operated on the basis of some pre-operative diagnoses such as kelloid, hematoma, suture granuloma, incisional herina and neoplasm. The most common symptom is cyclic and periodic pains in the area of operation which appear approximately 1-7 years after cesarean section. The accurate diagnosis is made by pathology. In this article a patient with cyclic and severe pain in cesarean scar area for 8 years is reported. The patient had been treated with anti- inflammatory drugs for several years without any diagnosis. The patient was operated with diagnosis of subcutaneous mass and probably suture granuloma and the final pathologic report was Endometriosis. The choice treatment for cesarean scar endometriosis is surgery, and awareness about this unusual complication of it will increase the probability of preoperative diagnosis.