Because precardiac disease seriously affects the quality of life and even the life expectancy of children, it should be detected, diagnosed and operated as early as possible, and the earlier the better. However, there are also rules for choosing the right time for surgery. In non-cyanotic precocious heart disease, if the child has good general development, is not susceptible to upper respiratory tract infections, and does not suffer from complications such as pulmonary hypertension, heart failure, or infective endocarditis, surgery can be performed at the age of 2 to 5 years. If the child is seriously ill, his general development is obviously affected, he often suffers from respiratory infections or even pneumonia, or he has complications such as pulmonary hypertension, heart failure or infective endocarditis, he should be operated as soon as the diagnosis is confirmed. Cyanotic precocious heart disease has a high mortality rate, therefore, children with cyanosis after birth should be examined by cardiovascular surgery as soon as possible, and once diagnosed, those who are in a position to do so should undergo primary radical surgery. For those who do not have the condition to undergo phase I radical surgery, they can first undergo reduction surgery to create conditions for phase II radical treatment. Some children with cyanotic preconditioning are born with unclosed ductus arteriosus to maintain their survival. Once the unclosed ductus arteriosus is closed, the mortality rate of the child will increase. The current success rate of surgery for common precocious heart disease is over 99%. Many children with precocious heart disease can live like normal people as long as they are operated in time, so there is no need for parents to worry or have other concerns. The timing of surgery for children with precocious heart disease cannot be determined by age and tolerance of surgery. However, some parents of children with precocious heart disease believe that their children are too young to withstand the trauma of surgery and that it is safer to wait until the child is older and stronger before performing surgery. Many people think that the child is superficially fine, so they delay the surgery time and time again, thus missing the best time for surgery, and some children even lose the opportunity for surgery, causing lifelong regret. The reasons for this situation are both parents’ lack of medical knowledge and non-specialist doctors’ lack of knowledge about precardiac disease. Parents are advised to bring their children to the hospital regularly for checkups to clarify the nature and extent of the heart malformation, and to let the specialist decide on the appropriate age for surgery, rather than waiting until they are older to avoid delays. Of course, the younger the child, the less tolerant of surgery, the greater the risk of surgery. However, if the heart malformation is complex or the lesion is serious, it can cause damage to the heart and lung function. Even if the heart malformation can be corrected by surgery later, the damaged heart and lung tissue function is difficult to recover, and even if the surgery is successful, it will not achieve the desired effect. The timing of surgery for precardiac disease should be decided according to the type of onset and the early or late appearance of symptoms, but for most patients with precardiac disease, the earlier the better. Arteriovenous ductus arteriosus, ventricular septal defect and atrial septal defect with large defect, high fractional flow, severe pulmonary congestion, often accompanied by complications such as heart failure and pneumonia should be operated early, and the surgery can be performed in infancy. In children with severe cyanotic preconditioning, such as tetralogy of Fallot, pulmonary artery port stenosis, and aortic port stenosis, who have frequent episodes of hypoxia, surgery should also be performed in infancy. If the condition is not very severe and cyanosis is present but does not affect life, surgery can be performed after 2 years of age. For severe cardiovascular malformations, such as misaligned aorta, complete pulmonary vein ectopic drainage, permanent arterial trunk, pulmonary atresia, aortic constriction and interrupted aortic arch, surgery should be sought as early as possible according to the different conditions of the child.