In terms of broad classification, congenital heart surgery is divided into closed surgery and direct cardiac surgery under extracorporeal circulation. Closed procedures are used for ligation of unclosed ductus arteriosus and aortic constriction angioplasty. In the lateral thoracotomy, the patient’s heart and lungs still perform their respective functions. Direct cardiac surgery under extracorporeal circulation, also known as open heart surgery, is the most commonly used method in which a median thoracic incision is made, the sternum is split, and the heart and lungs are restored by using an extracorporeal circulation machine instead of heart and lung function to stop the heart and resume it after repair. For example, septal defect repair, atrial septal defect repair, radical treatment of tetralogy of Fallot, etc. At present, there are still surgeries performed with the assistance of extracorporeal circulation machine to keep the heart still beating, such as atrial septal defect repair, which is more conducive to the recovery of myocardial trauma after surgery. In addition to intracardiac defect repair and valvuloplasty, there are still various special procedures for complex congenital heart disease, often named after the inventor. For example, the Rastelli procedure, the Fontan procedure, and so on, are used to address the correction of complex congenital malformations such as right ventricular double outlet, single ventricle, and tricuspid atresia. The optimal timing of surgery for congenital heart disease is one of the easiest questions to answer and the most difficult to answer. Generally speaking, in terms of the child’s ability to adapt to surgery, cooperate with postoperative treatment, and not interfere with learning, the best time is 3-6 years old, but it must be decided in the context of the specific disease and the patient’s specific situation. Some congenital heart diseases must be operated early, otherwise good surgical opportunities are lost, such as large ventricular septal defect, arteriovenous ductus arteriosus, due to a large number of left-to-right shunts, repeated pulmonary infections in infancy with heart failure, which is difficult to control by simple medication, often accompanied by severe pulmonary hypertension, so the operation should be completed early, generally within l years of age, or even less than half a year. However, for small and medium-sized ventricular septal defects within 2 years of age, if they are clinically asymptomatic, have little electrocardiogram effect, and have normal growth and development, they can wait until they are 2 years old for review before deciding to operate, because about 30-40% of membrane and muscle ventricular septal defects can close naturally with age. Although the current cardiac surgery technology and equipment, extracorporeal circulation, anesthesia level are very high, but after all, there are many complications, and even life-threatening, and the younger the age, the greater the difficulty, so the body growth and development of congenital heart disease and cardiac impact of smaller, such as atrial septal defect, small ventricular septal defect and arteriovenous ductus arteriosus is best to wait until an older age surgery is appropriate. The best age for surgery for tetralogy of Fallot is 3-6 years, but there is no age limit if an anoxic episode occurs. In cases of particularly severe cyanosis and poor pulmonary artery conditions, aortopulmonary artery diversion surgery may be considered to provide adequate pulmonary blood flow and promote pulmonary vascular development, followed by radical surgery within 1-2 years.