Behcet's disease ( BD) is a type of vasculitis with a chronic relapsing course that affects arteries and veins of all sizes. Intracranial aneurysms are rare manifestations. We report a patient with the diagnosis of BD, who had a fusiform aneurysm of the internal carotid artery at the level of the sinus cavernosus. He presented with sinus cavernosus syndrome findings. The aneurysm was treated endovascularly.