Primary mediastinal seminoma is a kind of germ cell malignancy outside the gonads, and it’s rarer with sarcoma component. hTis disease which has no special clinical manifestations and imaging characteristics is diffcult to identify with other mediastinal tumors and mediastinal type lung cancer. hTis paper reported a case of primary mediastinal seminoma with mediastinal sarcoma. hTrough the analysis of the diagnosis and treatment process in this patient, we will make a compre-hensive review of the disease.