Atrial septal defects and ventricular septal defects, referred to as atrial and ventricular defects both belong to the category of congenital heart disease. The first difference is that their anatomical parts are different. Our heart is a hollow muscular organ, which can be simply imagined as a two-story house. On the first floor, the right and left ventricles are next to each other, and on the second floor, the right and left atria are next to each other. Defects between the ventricles are called ventricular defects, and defects between the atria are called atrial defects. The second difference is that the severity of their consequences is not the same, generally the consequences of ventricular defects are more serious, his murmur is louder, the impact on the heart is greater, the impact on the child’s growth and development is also greater. This is manifested by growth retardation, frequent colds or lack of sports endurance, whereas atrial defects, unless they are huge, usually do not affect growth and development, and children are not prone to diseases, and the change in heart size is not too serious in the early stage. The third difference is that they also have different requirements for treatment. Ventricular defects require aggressive treatment. Atrial defects can also be observed if they are relatively small, and the treatment can be either interventional or surgical, depending on the specific anatomical structure.