A 31-year-old man presented with dull headache and memory disturbance lasting for one week. Computed tomographic scans revealed acute hydrocephalus. The cerebrospinal fluid contained 53 leukocytes/$mm^3$, with a mononuclear preponderance and no erythrocytes. Magnetic resonance imaging revealed hydrocephalus and leptomeningeal enhancement. Magnetic resonance angiography and digital subtraction angiography showed supraclinoid occlusion of the right internal carotid artery, which resembled unilateral moyamoya disease. Neuroendoscopic biopsy of a lesion in the septum pellucidum revealed noncaseating granulomas, which was consistent with sarcoidosis. The patient was successfully managed with intravenous methylprednisolone and ventriculoperitoneal shunting. To our knowledge, this is the first case of moyamoya-like vasculopathy associated with neurosarcoidosis.