报告２例原发性纵隔内胚窦瘤。均经组织病理学证实。ｌ例手术加术后化疗存活４个月，另１例手术切除肿瘤加术后放疗和化疗，已生存８个月。结合文献对本病病因、病理、临床表现、诊断、治疗及预后等进行了讨论。 Two cases of primary mediastinal endodermal sinus tumor were reported. All confirmed by histopathology. 1 case of surgery plus postoperative chemotherapy survived for 4 months, another case of surgical resection plus postoperative radiotherapy and chemotherapy had survived for 8 months. Combining the literature, the etiology, pathology, clinical manifestations, diagnosis, treatment and prognosis of the disease were discussed.