Ovarian surface epithelial tumors with choriocarcinomatous differentiation are vary rare. We report a case of clear cell carcinoma of the ovary with choriocarcinomatous differentiation in a 54-year-old female who got admitted for evaluation of a large pelvic mass. Clinically, mass arising from right adnexa/ soft tissue/ appendix was suspected which on radiologically showed a solid and cystic mass arising from right adnexa. The mass was excised in toto and sent for histopathological examination. Grossly, we received a salphingo-opherectomy specimen measuring 13x11x8 cm. External surface was smooth with congested blood vessels. Cut surface revealed solid (40%) and cystic (60%) areas and reddish brown fluid was extruded. Friable and hemorrhagic areas were noted grossly. Microscopy revealed sheets of clear cells the lesion was composed of round to oval cells with ill defined cell border, moderate eosinophilic to clear cytoplasm and bland nuclei. A panel of Immunohistochemical markers were performed and the lesional cells were positive for Pax 8 and beta HCG .With H&E morphology and Immunohistochemical staining pattern a diagnosis of clear cell carcinoma of the ovary with choriocarcinomatous differentiation was rendered.