Intracardiac metastasis as the initial presentation of malignant neoplasm is very rare. We report here on a 64-year-old man with non-small cell lung cancer (NSCLC) initially presenting with intracardiac metastasis which was identified with 18-F fluorodeoxyglucose positron emission tomography (FDG PET). The patient was admitted with complaints of exertional dyspnea and vague chest discomfort that had developed a few weeks ago. Two-dimensional echocardiography revealed a heart mass attached to its akinetic wall in the right ventricular chamber. CT and MRI demonstrated a large tumor involving the epicardium and myocardium in the right ventricle, and there was a mass in the right lower lobe of the lung along with multiple lymphadenopathies. Cytologic examination of the percutaneous needle aspiration of a lymph node in the anterior mediastinum revealed malignant epithelial cell nests, and this was strongly suggestive of squamous cell carcinoma. Subsequent FDG PET confirmed that the intracardiac mass had an abnormally increased FDG uptake, and again this was strongly suggestive of malignancy. By systemically considering these imaging studies, we were able to diagnose the mass as intracardiac metastasis of NSCLC.