Primitive neuroectodermal tumor (PNET) is a small round tumor belonging to the PNET/Ewing's sarcoma family. We hereby report a case of PNET of the ovary, which was detected at the second trimester of pregnancy. Chemotherapy was administered and a healthy baby was delivered by cesarean section. After the pregnancy, the mother was found to have metastatic disease. Chemotherapy was continued, but she died due to progressive disease 13 months after the initial diagnosis. In this case report, we discuss chemotherapy options during pregnancy and the importance of multidisciplinary approach to unusual presentations of rare tumors.