A 35-year-old man was admitted to Korea University Anam Hospital for evaluation of intermittent chest pain. Computed tomography of the chest showed enlargement of a previously identified anterior mediastinal mass and also a well-defined, circumscribed mass in the subcarinal area, surrounded by the roof of the left atrium, right pulmonary artery, and the carina. Complete resection of the intrapericardial tumor was performed through median sternotomy without cardiopulmonary bypass. Pathologic examination identified the tumor as schwannoma, of an ancient type, diffusely positive for the S-100 antigen. Unlike other reported cases, grossly, the tumor did not seem to be involved with any nerve.