Heart arrhythmia (also known as arrhythmia, dysrhythmia or irregular heart beat) is a group of conditions in which the heart beat is irregular, too fast or too slow. Many types of arrhythmia have no symptoms. When symptoms are present, these may include palpitations or feeling a pause between heart beats. Unlike the adult population, arrhythmias occur less commonly in childhood. Only 5% of the emergency hospital admissions in the paediatric population is attributed to symptomatic arrhythmias. There were arrhythmias with an incidence of 140:100 000 at Emergency Department presentations. The arrhythmia or conduction abnormalities incidence were 1.25% of elementary school students and 2.32% of junior high school students. An arrhythmia can occur as a result of internal factors, such as a disease of the heart muscle it self (cardiomyopathy) or a heart defect the child had when he or she was born (congenital heart disease). Other common causes of arrhythmia in children include: infections. The most common pediatric arrhythmias, including sinus arrhythmia, premature beats, brady-arrhythmias, escape rhythms and tachy-arrhythmias including different types of atrial, junctional and ventricular tachycardias.The symptomatology of arrhythmias in children depends on the underlying rhythm disorder and the age at presentation. Typically, neonates and infants with arrhythmias tend to present with congestive cardiac failure secondary to tachycardiomyopathies. This is particularly known to occur following PJRT, AET and VT. Palpitation and or syncope are the mode of presentation in older children. Complete heart block is the bradyarrhythmia of significance seen in childhood. This is either of congenital etiology or a sequela to cardiac surgery. Infrequently,sudden cardiac death (SCD) occurs due to arrhythmias particularly when they are of ventricular origin. SCD of arrhythmogenic etiology in children is reported with HCM, LQTS, Type B WPW syndrome, complete heart block and ventricular arrhythmias post cardiac surgery. The diagnosis of arrhythmia was made with hidtory taking,physical examination,electrocardiography trcord,echocardiography examination,and electrophysiology study. The management of arrhythmia is depend on the diagnosis and severity of the disease. The management  consist of medical,electophysiology ablation and device implantation.