There are various microbial agents which causing meningitis in children. It is well known that Haemophilus influenzae (HI) are the most frequent bacterial agents. In Korea, it is hard to find studies detecting HI in cerebrospinal fluid (CSF) from pediatric patients with aseptic meningitis by PCR. It has been also reported that human herpes virus-6 (HHV -6) causes meningitis, meningoencephalitis, neuroinvasion and persistent infection of the central nervous system in children. In this study we also detected HHV-6 in the same CSF by EIA and PCR. We used 85 CSF specimens from 85 aseptic meningitis patients (mean age 6.6 years) taken from the Department of Pediatrics at Ewha Womans University MokDong Hospital from June 2001 to August 2002. Detection rate of HI by EIA method was 12.9% (11/85) and by PCR was 16.5% (14/85). Detection rate of HHV-6 by EIA and by PCR was 18.8% (16/85) and 21.2% (18/85), respectively. Co-detection rate of HI and HHV-6 was 7.1% (6/85) by EIA and 12.9% (11/85) by PCR. In conclusion, by PCR in combination with EIA, HI infection could be proved in the aseptic meningitis CSF from which no bacterium was cultivated.