Large cell neuroendocrine carcinoma of the ovary is rare, aggressive neoplasm frequently accompanied with surface epithelial tumor. A 47-year old woman with asymptomatic pelvic mass which showed malignant on frozen biopsy underwent total hysterectomy, bilateral salpingo-oophorectomy, pelvic and para-aortic lymphadenectomy, partial omentectomy, appendectomy. Pathologically, size of the pelvic mass was 11 cm in greatest diameter with surface rupture. Histology and immunohistochemical staining revealed that large cell neuroendocrine carcinoma accompanied with malignant brenner tumor and serous adenocarcinoma. Under the diagnosis of Ic ovarian cancer, patient received six cycles of taxol and cisplatin. After a follow-up 2 years, she shows no evidence of disease.