Mediastinal Germ cell tumors are extragonadal germ cell tumors (EGGCTs) commonly seen in children and young adults. Other extragonadal sites that has been detected includes the presacral area, the face, uvula, and the pineal gland. Yolk sac tumor (endodermal sinus tumor) is a subtype of germ cell tumor and a highly malignant neoplasm. Primary yolk sac tumor of the anterior mediastinum is an extremely rare case and carries a grave prognosis, affecting mainly young men. We present a 27- year- old male with primary yolk sac tumor of the anterior mediastinum.