A case of a 44-year-old female who had an intrathoracic mass that was found to be a hemangiosarcoma of the anterior mediastinum is reported. Radical surgical incision through a right anterior thoracotomy was performed, followed by post-operative radiotherapy. Since this is a rare tumor at this location, the clinical and radiological findings, the histopathological appearances and its therapeutic management are discussed. Radiologists, surgeons and oncologists should in the differential diagnosis of a mediastinal mass include that of a tumor of vascular origin, even if it is rare. Radical excision followed by post-operative radiotherapy, especially in cases where the tumor has been partially excised, is the treatment of choice.