BACKGROUND: Herpes simplex virus type 2 (HSV-2) is the second most common cause of viral meningitis and the most common cause of recurrent meningitis. Although the incidence of HSV-2 meningitis is high, its clinical characteristics are not well known. The purpose of this study was to review the clinical characteristics and prognosis of HSV-2 meningitis. METHODS: We analyzed patients who were admitted to the Department of Neurology at Severance Hospital with a final diagnosis of HSV-2 meningitis, as confirmed by applying the polymerase chain reaction to the cerebrospinal fluid (CSF) of patients. RESULTS: The study involved 998 patients with aseptic meningitis and 60 patients diagnosed with HSV-2 meningitis. The mean age at meningitis presentation was 32.5 years (range 18-54 years), and 72% of the patients were female. Common clinical symptoms were headache (100%), nausea and/or vomiting (83%), meningismus (57%), and fever (55%). Six patients had a history of genital herpes infection, and 11 had a past history of recurrent meningitis. The CSF study was notable for elevated protein (111.0±53.5 mg/dL, mean±standard deviation) and white cell count (332.0±211.3 cells/µL). The CSF/serum glucose ratio was 0.52±0.90. Various treatments were applied, including conservative care, antiviral agents, empirical antibiotics, and combined treatments. All patients recovered without serious neurologic sequelae. CONCLUSIONS: HSV-2 meningitis is relatively common, as are recurrent episodes. The clinical characteristics of HSV-2 meningitis are similar to those of other types of aseptic meningitis. HSV-2 meningitis is treated using antiviral therapy, and the prognosis is favorable even with conservative treatment.