This is a case report of a 41-year-old man with Behçet's disease who suffered from cerebral infarction due to complete occlusions of the bilateral internal carotid arteries. His illness began at age 23 with blurred vision of the right eye. The last few years he complained of recurrent painful ulcers on the mucosa or skin of the mouth and the external genitalia. In August 1998, he was admitted to our hospital in an acute confusional state with right hemiplegia. Head CT scans and MRIs revealed acute and subacute ischemic lesions in the left frontal lobe and some other regions of the bilateral hemispheres. Carotid angiography showed complete occlusions of the bilateral internal carotid arteries just rostral to the bifurcations. He did not have any histories of hypertension nor other risks for cerebrovascular diseases. Although direct evidence for the cause of carotid occlusions was not obtained, we speculated that his cervical lesions came from the arterial changes attributable to vasculo-Behçet's disease. Vascular involvements are not infrequent in Behçet's disease, but we believe such occlusive lesions in the bilateral internal carotid arteries as seen in our case are extremely rare. As a construction worker he had undergone a lot of mechanical stress on his neck, which might be a trigger for the carotid lesions.