We present a case of hydrocephalus as the primary manifestation of neurosarcoidosis. Sarcoidosis is a rare disease in Korea and its incidence is much lower than that of tuberculosis. Diagnosis is made by pathologic findings and by exclusion of other granulomatous disorders. Neurosarcoidosis is observed in approximately 5% of sarcoidosis. Its common manifestations are facial palsy (50% of patients with neurosarcoidosis) and optic neuritis. Hydrocephalus is a very uncommon reported finding. Although the typical presentation of sarcoidosis such as facial palsy is not a diagnostic dilemma, more atypical presentations such as hydrocephalus with altered mentality in a tuberculosis patient can lead to a misdiagnosis.