Acute renal failure (ARF) is a significant cause of morbidity and mortality in children. It may be pre-renal, intrinsic, or post-renal (obstructive) in aetiology. ARF was investigated in children in the south-southern part of Nigeria to determine the prevalence, aetiology, management and outcome of ARF. A retrospective review of data from all children from birth to 16 years of age admitted into the Department of Paediatrics, University of Port Harcourt Teaching Hospital (UPTH), with the diagnosis of ARF over an 18 year period (January 1985 to December 2003) was performed. Information was obtained about the age, sex, clinical features, blood pressure, laboratory and radiological investigations, aetiology, and treatment received including dialysis. Information on the outcome, factors influencing outcome, and possible causes of death were reviewed. There were 211 patients, 138 (65.4%) males and 73 (34.6%) females (M:F, 1.9:1), with a hospital prevalence of 11.7 cases/year. The patients were aged 5 days to 16 years (mean 5.6+/-4.7 years). Oliguria was the most common clinical presentation in 184 (87.2%) patients. Hypertension was seen in only 39 (18.5%) patients. The causes were age-related. The neonates had ARF from severe birth asphyxia 27 (35.5%), septicaemia 17 (22.4%), with tetanus 4 (5.3%) and congenital malformations 11 (14.5%). Sixty-one (28.9%) and 29 (13.7%) patients had ARF from gastroenteritis and malaria respectively. The patients with leukaemia were all more than 10 years old and had acute lymphoblastic leukaemia. Two patients (1.9%) had Burkitts lymphoma involving the abdomen and 3 patients had HIVAN. 112 (53%) patients had anaemia with a mean haematocrit of 20.25+/-6.9%. Dialysis was indicated in 108 patients, but only 24 patients (22.2%) had peritoneal dialysis (PD), because of financial constraints and lack of dialysis equipment. Mortality rate was 40.5%. The causes of death were uraemia 60 (70.6%), overwhelming infection 5 (5.9%), and recurrent anaemia 20 (23.5%). Hypertension (X2 15.7, P<0.001) and lack of dialysis (X2 7.96, P<0.01) significantly affected outcome. Other factors associated with demise were delayed presentation (58.8%), use of herbal treatment (35%), and unaffordability of treatment (40%). ARF is a significant cause of mortality in Nigerian children. The patients are not adequately managed because of poverty and lack of facilities for dialysis. The causes of ARF in our environment are preventable, and should be expected.