PURPOSE: This study was conducted to establish the prevalence and clinical features of WPW- type ventricular preexcitation syndrome in children. METHODS: Eighteen patients were discovered by the mass heart disease screening using ECG on 47,691 elementary school children in Kwangju from September 1992 to December 1994 (group 1), and 14 patients were diagnosed at the Department of Pediatrics, Chonnam University Hospital from 1991 to August 1995 (group 2). We retrospectively reviewed patients' medical records. RESULTS: The prevalence rate was 4 per 10,000 elementary school children and there was no sexual difference. All patients in group 1 were asymptomatic, but 5 patients in group 2 had symptoms related to tachyarrhythmias. Three patients with WPW syndrome and paroxysmal supraventricular tachycardia who underwent radiofrequency catheter ablation have been well without recurrence of tachyarrhythmias during the follow-up period of 29-45 months. Two cases in group 2 had structural cardiac lesion (ventricular septal defect in 1, mitral valve prolapse in 1). CONCLUSION: The prevalence rate of Koreans was lower than that of foreigners. The radiofrequency catheter ablation seemed to be relatively safe and effective for the treatment of atrioventricular reentrant tachycardia utilizing accessory pathway in childhood patients if this procedure is technically feasible. However, continuous longitudinal studies are needed to evaluate the long-term natural history and prognosis of the WPW-type ventricular preexcitation syndrome.