TO know the causative agent of asptic meningitis. we performed and cerebrospinal fluid study on 24 children who had been admitted to the department of Pediatrics.. Asam Medical Center form Jume. 1991 to July 1991. In the 10 cases of them. CSF virus culture was done Special Reference Laboratory, Japan The most of the patients were young infants, and 15 cases of them were under 3 months of age. The male to female ratio was 1:1.4 We observed the main symptoms as fever 100%. irritability 67%, vomiting 17%. poor feeding 13%, seizure 8%. In the 4 cases among the 10 cases with virus culture, Coxsackievirus B5 was cultured. We concluded that the causative agent of this epidemic aseptic meningitis in 1991 was Coxsakievirus B5.