Objective. To investigate the effect of peritoneal dialysis on fluid balance and outcome in children who receive cardiac operation.Methods. From July to Dec. 2000

12（2.08%） patients of 576 consecutive children who underwent heart operation required peritoneal dialysis because of acute renal failure. The mean age of these 12 patients was （2.9-2.0） years （range

5 months-7 years） and the mean body weight was （12+3） kg （range

7.4-18.5 kg ）.Results. The interval between the operation and the initiation of peritoneal dialysis was （21.2+11.4） hours （4.4-42 hours）. The duration of peritoneal dialysis was （6.3+4.8） days （0.47-15 days）. Mortality in these 12 patients was 25%. Fluid removed by peritoneal dialysis was（34.7+17.8） ml . kg-1 . day-1. Asymop-tomatic hypokalemia

thrombocytopenia and hyperglycemia were frequent complications

which were easily managed. Hemodynamics and pulmonary function improved during the study period.Conclusion. The early initiation of peritoneal dialysis is an effective and safe method to treat acute renal failure after cardiac operation in children.