Functional univentricular is a complex congenital heart disease in which one ventricle cannot assume its pumping function and is anatomically impossible to correct with biventricular correction. The heart does not have two well-developed ventricles and is one of the most challenging congenital cardiac malformations to treat. It is challenging to treat both medically and surgically. In a functional single ventricle heart, there is most commonly an incomplete hypoplastic or dysplastic ventricle with no atrioventricular connections. The development of palliative and reconstructive cardiac surgery has had a significant impact on the life expectancy and quality of life of these patients. The 10-year mortality rate in patients with functional univentricular disease without surgical intervention is 40%, with causes of death including heart failure, AV regurgitation, and arrhythmias. The Fontan procedure is a proven method for maintaining normal physiologic circulation in patients with functional univentricular disease. This surgical approach is physiologically corrective and can significantly improve the patient’s hypoxic state, with significant postoperative improvement in cyanosis, significant improvement in cardiac function, and significant improvement in quality of life. Huang Jiezhou, Department of Cardiac Surgery, The First Hospital of Guangzhou Medical University