Abstract :Extra Gonadal Germ Cell Tumors (EGGCT) are germ cell neoplasms with morphologic, serologic and cytogenetic features similar to those seen in gonadal tumors, but occurring outside the gonads (ovary and testis). These tumors (EGCT) are rare and account for 1% to 5% of all germ cell malignancies. In adults, the most common locations of primary extra gonadal germ cell tumors by their frequency of occurrence are the mediastinum, retroperitoneum, sacrococcygeal and the pineal region. However, isolated cases of EGCT have been reported in other organs such as thyroid, pericardium, liver, bladder, breast, urachus and vulva. We describe a case of primary malignant germ cell tumor of the uterus, endodermal sinus type (yolk sac tumor) with hepatoid differentiation. Immunohistochemistry showed strong positive staining for PLAP, AFP, HEPPAR-1 and GPC3. HCG stain was positive in the large multinucleated tumor cells. ER and PR were negative. Endodermal sinus tumors with predominant or pure hepatoid patterns are extremely rare and occur more frequently in the ovary. The presence of a hepatoid differentiation confers aggressive behavior and poor prognosis. Recognition and distinction between this entity and other primary endometrial tumors is important to provide appropriate therapy for the patient.