OBJECTIVE Neisseria meningitidis usually causes severe infection in children, but occurs only sporadically in Taiwan. However, the number of infections increased in 2001 and 2002. This study was performed to ascertain the epidemiology and clinical manifestations of infections caused by meningococcus in a pediatric population. METHODS The medical charts of patients with meningococcal diseases who were admitted to Chang Gung Children's Hospital, Taoyuan, Taiwan, from July 1998 to December 2005 were retrospectively reviewed. Data were analyzed for age distribution, serogroups, clinical diagnoses, treatment, acute complications, and outcomes. RESULTS Sixteen children with meningococcal disease were identified. Their ages ranged from 1 month to 15 years (average, 3 years). Most patients (62.5%) were younger than 1 year and the second most frequent age group was 6 to 15 years (18.75%). There were 56.25% boys and 43.75% girls. The identified serogroups were B (43.75%), W135 (31.25%), A (6.25%), Y (6.25%), and undetermined (12.5%). The antibiotics used in this study were ampicillin, ceftriaxone, cefotaxime, and aqueous penicillin; the mean total treatment duration was 10 days. Purpura fulminans (37.5%), disseminated intravascular coagulopathy (31.25%), respiratory failure (25.0%), and shock (25.0%) were the commonest acute complications. Most (87.5%) of the patients survived. One patient had long-term sequelae of hearing impairment and speech delay. The mortality rate was 12.5%. CONCLUSIONS Serogroup B and W-135 were 2 predominant serogroups to cause pediatric meningococcus, and the majority of infections occurred in children younger than 1 year. Continuous surveillance and prevention of meningococcal infections are of great importance.