A total of 231 children with acute appendicitis were treated at our hospitals during the 10 years between 1984 and 1993, 53 of whom had a perforated appendix. These 53 patients were randomly assigned to two groups at the time of surgery according to the different procedures performed. Thus, 29 children were managed by appendectomy followed by peritoneal lavage using a large amount of saline, and intravenous antibiotic therapy consisting of aminoglycoside and cephem (lavage group), while the other 24 children were treated by appendectomy with silicon tube drainage and the same systemic antibiotic therapy (drainage group). The mean length of hospitalization, and the mean durations of fever and the need for fasting after laparotomy in the lavage group were significantly less than those in the drainage group: 10.1 versus 18.8 days, 2.8 versus 7.7 days, and 1.8 versus 3.5 days, respectively. The operation wounds healed well in the lavage group due to the fact that there was no drain. Wound infections occurred in two children from the lavage group and six from the drainage group. Intra-abdominal abscesses occurred in two children from the drainage group. Accordingly, peritoneal lavage appears to be superior to intraperitoneal tube drainage for the management of perforated appendicitis in children.