Atrial septal defect, a type of congenital heart disease, is a condition in which an orifice appears between the left and right atria that should not be there, causing a mixture of blood from the left and right heart, which seriously affects the hemodynamics of the body and human health. On the ultrasound diagnosis of atrial septal defect, the atrial septum can be seen to form a left-to-right shunt from the foramen ovale, and abnormal blood shunts can be seen, as well as elevated pulmonary hypertension and reduced heart function in the child, by which the diagnosis of atrial septal defect can be determined. Once this condition is present, surgical treatment is required. Prior to treatment, relevant ancillary tests need to be completed in order to develop the next treatment plan so that the child can achieve health faster.