OBJECTIVE To investigate the etiology and outcome of fulminant hepatic failure (FHF) in children. METHODS Hospital based descriptive. METHODS 36 children (22 males and 14 females) presenting with FHF over a period of one year were investigated. The ages ranged from 1.5 to 9 years. FHF was defined as occurrence of encephalopathy within eight weeks of onset of jaundice with no evidence of pre-existing liver disease. Detailed history, clinical examination, routine biochemical parameters and relevant diagnostic tests were carried out. Viral markers studied were anti HAV-IgM, HBsAg, anti HBc-IgM, anti-HCV and anti HEV-IgM. RESULTS A viral etiology could be established in 22 children (61.1%). Hepatitis A (n = 12), Hepatitis B (n = 3), Hepatitis A and B (n = 2), and Hepatitis A and E (n = 4). Two children had enteric fever (1 with associated HEV), 2 children had Wilson's disease, 1 child had Indian Childhood Cirrhosis (ICC) and 2 children had drug induced hepatitis. Etiological diagnosis was not possible in 8 children (22%). Fourteen children (39%) died. Poor outcome was associated with spontaneous bleeding, raised prothrombin time, lower transaminases and higher bilirubin on admission. CONCLUSIONS Viral hepatitis is the commonest cause of FHF in children. HAV alone or in combination is responsible for upto 50% of all FHF in children. Chronic liver disease can also present as FHF. Etiological diagnosis is not possible to upto one-fourth of all cases.