A 65-year-old male who presented with dizziness, dysarthria, and disability of his left hand was admitted to our hospital. Magnetic resonance imaging of the head revealed cerebral infarction and enhanced computed tomography revealed a suspicious thrombus in the ascending aorta. He did not have a coagulation disorder. We performed ascending aortic replacement and removed the thrombus with the aortic wall in order to avoid any recurrences. Here we report the successful treatment of the case from clinical and pathological points of view with some findings.