This retrospective study included 18 pediatric cases (median age, 3 years) with pathologically proved hemophagocytic syndrome (HPS) from a single institution during 1992 and 2001. There were 9 males and 9 females. Prolonged fever, cytopenia, liver dysfunction and hepatomegaly were the most common features at presentation. Sixteen (88.9%) cases were previously healthy. The case fatality rate was 61.1%, and all fatal cases died within 2 months of disease onset. The infectious agents associated with HPS were identified in 11 cases (61.1%), and 8 (72.7%) of them had evidence of Epstein-Barr virus (EBV) infection or reactivation. Underlying immunologic disorder or neoplastic disease was identified in 11.1% of the cases. Children less than 3 years of age with HPS were more vulnerable to neutropenia-associated bloodstream infection (85.7% vs 27.3%; p=0.025). Pseudomonas aeruginosa (3) and Candida tropicalis (2) were the 2 most commonly isolated pathogens. Regarding specific management of HPS, intravenous immunoglobulin and steroids were the first-line agents and were administered in 16 cases and 11 cases, respectively, while etoposide was administered in 5 refractory cases during the late phase of disease. Most HPS occurred in previously healthy children, and a substantial proportion of cases rapidly progressed to death. Most cases were associated with viral infection, particularly EBV, and young children tended to develop neutropenia-associated bacteremia during the active phase of the disease.