BACKGROUND AND OBJECTIVES: Herpes zoster(HZ) is a well known viral infection of the nervous system. HZ is associated with the neurologic complication. It may have been expected a change in the cerebrospinal fluid(CSF) of patients with HZ. The purpose of this paper is to present the correlation between CSF findings and neurologic complications in HZ. METHOD: The patients(n=75) with HZ were 31 male and 26 females, who were ranged in age from 15 to 79years(mean 53.4 years) admitted to department of Neurology of Chung Ang Gil General Hospital from June 1992 to May 1995. The patients were evaluated for the etiology, lesion distribution, and complications. CSF study was performed in 32 patients(male/female=20/12), whose age ranged from 16 to 79 years(means 51years) during 5 days to 10days after initial symptom onset. CSF findings were analyzed for their etiology, lesion distribution and complication. RESULTS: The CSF of 25 patients(78.1%) showed pleocytosis(5 to 49/mm3 in 10 patients, means, 62.1/mm3). 7 patients(12.3%) had meningitis symptoms, whose cell counts of CSF were more than 50/mm3(means 128.4/mm3) postherapeutic neuralgia was more common in elder patient than younger patients(p=0.005). Complications tended to correlate with the cell counts of CSF. There was no difference in CSF finding between cranial segmental involvements. CONCLUSION: We confirmed the pleocytosis in CSF of patients with HZ and suggest the development of complications in patients in patients with HZ tend to correlate with the cell counts of CSF.