<h3>Introduction/Background</h3> Endometriosis can occur in extra pelvic locations. Abdominal wall endometriomas (AWE) usually occur as a secondary process to gynecological surgeries, most often caesarean, with an incidence between 0.03 to 0.45% and only 1% can be malignant. <h3>Methodology</h3> 34-year-old patient who consulted due to dysmenorrhea, antecedent of two caesarean, to physical examination with nodular lesion in abdominal wall in relation to surgical scar, Ca 125: 696.60, pelvic ultrasound normal, in Abdominal and pelvic resonance of thickening and distortion of the straight muscles in the suprapubic region of the abdominal wall, conglomerate 84 * 68 * 39 mm. The diagnosis of AWE is made, she´s carried out to resection where a 10 x 15 cm lesion is evidenced, pathology report a moderately differentiated adenocarcinoma of endometrioid appearance. The rarity presentation of a primary endometrioid adenocarcinoma in the abdominal wall, possible endometrial or ovarian origin are studied. She´s led to gynecological curettage reported as negative for hyperplasia / malignancy, CT scan with adnexal cystic lesion, primary ovarian is suspected, is decided to cytoreduction. Pathology report: adenomyotic uterus, parametria with endometriosis, 72 lymph node free of tumor. She´s assessed by clinical oncology and before non-standard management, decided clinical observation without evidence of tumor after 8 months of follow-up. <h3>Results</h3> It was considered a rare case of a primary endometrioid adenocarcinoma of the abdominal wall and the most common histological type is clear cell adenocarcinoma (62%). The histopathological criteria of Sampson-Scott, such as the coexistence of benign and malignant endometrial tissue in the tumor, histological appearance consistent with endometrial origin and excluding another primary tumor site allow to confirm the diagnosis. <h3>Conclusion</h3> The malignization of the AWE is a rare clinical entity and the histological type endometrioid is even more rare, in terms of management wide local excision with free margins is the key point to prevent recurrence. <h3>Disclosure</h3> Nothing to disclose