We undertook a retrospective study of the risk factors determining outcome of nontraumatic patients with shock in the pediatric emergency service. From October 1992 through September 1997, 22 patients with the diagnosis of shock were identified, including 11 with septic shock (50%), 7 with hypovolemic shock (32%) and 4 with cardiogenic shock (18%). Their age ranged from 2 months to 19 years old. Among the cases, 14 patients (64%) had other underlying diseases. Gram-negative bacterial sepsis (6/11, 55%), dilated cardiomyopathy (2/4, 50%) and acute gastroenteritis (7/7, 100%) were the most frequent causes of septic, cardiogenic and hypovolemic shock, respectively. In total, 12 patients (55%) died. The mortality rate was high in septic shock (9/11, 82%) and cardiogenic shock patients (3/4, 75%), but low in hypovolemic shock patients (0/7, 0%). The risk factors of poor outcome in patients with shock included thrombocytopenia, prolonged prothrombin time and partial thromboplastin time. Patients with leukopenia, a higher level of C-reactive protein, or under 2 years of age tended to have poor outcome.