Objective: to study the causes of acute renal failure (ARF) in children and to substantiate recommendations on its treatment. Fifty-nine children with ARF were followed up in 1979 to 2004. In 90% of the patients, ARF was established to be caused by hemolytic uremic syndrome (HUS), acute intestinal infection (AII), acute glomerulonephritis, and acute intravascular hemolysis. The major cause of ARF was AII in two thirds (66.1%) of the children. In the past decade, the incidence of HUS has decreased from 55 to 40%. The authors identified the following predictors of poor ARF outcome: early age, anuria, impaired consciousness progressing to spoor and coma. A combination of these symptoms is most frequently observed in patients with HUS in which the kidneys are the major target organ and the possibilities of more than 7-day treatment for anuria without dialysis are limited. In other etiology of ARF, water deprivation, antihypertensive therapy, and exchange plasmapheresis allow patients to survive until renal function restores without renal replacement therapy, by preventing serious complications.