We present a rare case of an 8-year-old boy with a solitary large tumor in the right upper thoracopulmonary region. The tumor was pathologically confirmed to be an extraosseous Ewing sarcoma. To our knowledge, only a few cases of primary thoracopulmonary extraosseous Ewing sarcoma have been reported. We also discuss a broad spectrum of diseases that can be included in the differential diagnosis of an intrathoracic mass.