Primary hepatoid carcinoma of the ovary (HCO) is a rare type of ovarian tumor that resembles hepatocellular carcinoma both histologically and immunohistochemically in its staining for alpha-fetoprotein (AFP). We describe a 51-year-old woman who presented to our hospital complaining of abdominal pain. Computed tomography scan revealed a large tumor in the pelvis. She underwent total hysterectomy and bilateral salpingo-oophorectomy with tumorectomy. A right ovarian mass measuring 9×8×6 cm was found. Histological diagnosis was hepatoid carcinoma of the right ovary. But, immunohistochemically, tumor cells were not immunoreactive for AFP and there was no elevation of serum AFP level. This is the first report of an ovarian carcinoma with typical histologic features of HCO with negative staining for AFP and normal level of serum AFP in the world.