Congenital heart disease needs to be diagnosed based on medical history, symptoms, signs and findings of ancillary tests. Most children are diagnosed with heart murmurs on physical examination, while some children are diagnosed with reduced crying and cyanosis, and some children with vascular rings are diagnosed with cardiac malformations on ultrasound due to long-term coughing and wheezing. At present, cardiac ultrasound can clearly diagnose most congenital heart diseases, and auxiliary examinations can include chest X-ray and electrocardiogram, which are mainly used to observe the development of pulmonary vessels and the size of each atrium. With the development of 64-row CT technology, enhanced CT can definitively diagnose congenital heart disease, but because of the hazards of receiving radiation and because cardiac ultrasound can meet most of the clinical needs. Therefore, only some congenital heart diseases require further enhanced CT. For example, the observation of pulmonary vascular development and collateral vascularity in severe tetralogy of Fallot. Complete pulmonary venous ectopic drainage is observed for pulmonary venous return pathways and the presence of obstruction. Similarly, cardiovascular angiography can diagnose congenital heart disease, but because it is an invasive test and requires radiation. It is currently used only in special cases such as when pulmonary artery manometry is required.