Endometriosis is defined as a functional endometrial tissue outside the uterine cavity. The ectopic endometrial tissue has been identified after gynecologic laparoscopy or laparotomy procedures in the skin, subcutaneous tissues, abdominal and pelvic wall musculature, and it represents amayor cause of acute or chronic recurrent abdominal or pelvic pain resembling the menstrual cycle. The frequency of abdominal wall endometriosis is approximately 1% of all women who had a cesarean delivery. A 39-year-old patient with a history of one prior Cesarean section, presented with continuous cyclical focal pain at the left part of cesarean scar site for the past 16 months, 23 months after Cesarean section. The patient underwent a mini laparotomy, when endometrioma was completely removed surgically. The PH diagnosis of endometriosis was based on the presence of all elements of the endometrial mucosa (glands, stroma and signs of fresh and old hemorrhage) in an inadequate place (anterior abdominal wall). Endometriosis is difficult to diagnose and it is often mistaken for other conditions such as a suture granuloma, incisional hernia, primary or metastatic cancer. Endometriosis can be prevented only with good surgical techniques and clinical practice as well as the proper care during primary surgery.