We report a rare and unique case of possible extrapulmonary tuberculosis in an 83-year-old man who had cardiac tamponade and paroxysmal atrial flutter. The patient was admitted to our hospital because of syncope. The cardiac tamponade and paroxysmal atrial flutter were treated by pericardiocentesis and drainage of bloody pericardial fluid. Mycobacterium tuberculosis was not detected in diagnostic specimens, nor was any evidence of malignancy found. The remarkable elevation of adenosine deaminase and the predominance of lymphocytes in the pericardial fluid, considering the past history of tuberculosis, led to a diagnosis of extrapulmonary tuberculosis. After receiving standard antituberculous therapy by ethambutol, isoniazid, and rifampicin, the patient recovered and has remained well up to the present day. Thirty-six months have passed since his recovery without the recurrence of cardiac tamponade or any other cardiac events.