Holter monitoring (HM) is widely used in arrhythmic disorders of adult patients; however, studies in the pediatric age group are limited. This study aims to determine the value of HM in diagnosis and treatment of disorders related to arrhythmias in pediatric patients. We examined 2,017 Holter records of 1,500 children who applied to our institution between November 1994 and October 1998. The age ranged from 0-24 years (52% male, 48% female). The indications for HM were screening for arrhythmic symptoms (palpitation, chest pain, syncope) in 67 percent, monitoring dysrhythmic therapy in 17 percent, postoperative control in five percent, and pacemaker control in four percent. Palpitation is the leading presenting symptom, with more frequent findings of supraventricular extrasystole (SVE), supraventricular tachycardia (SVT), ventricular extrasystole (VE) and complete heart block (CHB) when compared to other symptoms. Only 5.3 percent of the patients had arrhythmic symptoms during monitoring and asymptomatic patients had more frequent arrhythmias. SVT, VE, and CHB are more frequent findings in the abnormal heart with previous cardiac operations. The diagnostic yield is low with arrhythmic symptoms in the pediatric age group; however, HM enables cumulative evaluation of heart rhythm and rhythm variability, which is important in diagnosing silent arrhythmias in high risk groups (abnormal heart, postoperative heart).