A 25-year-old woman with a stage IA pure embryonal carcinoma of the left ovary, without elevated serum markers namely AFP and HCG (nor-positive immuno-histologic marking at the later pathological analysis) underwent surgery alone (unilateral salpingo-oophorectomy). She relapsed seven weeks later with peritoneal carcinomatosis. She still did not have elevated tumor markers. She then received five courses of a cis platinum-based chemotherapy (bleomycin, etoposide and cisplatinum, BEP) and achieved pathological complete response (as attested by a coelioscopic third look). This response is still lasting, fourteen months after the end of the procedure. Malignant ovarian germ cells tumors account for 2 to 5% of all ovarian cancers and embryonal carcinoma is rare. It may be associated with high serum levels of AFP and/or HCG, but not when the embryonal carcinoma is really pure. These markers are very helpful for patient follow-up but not in our patient's history. These tumors offer a very good chemosensitivity especially when treated with cisplatinum. This treatment dramatically improved their prognosis and extensive debulking surgery is yet unnecessary. Some questions still remains is there any specificity for embryonal carcinoma within malignant germ cell tumors of the ovary group? What is the best treatment for stage IA disease? When is a surgical second look (or a third look as for our patient) justified?