The causes of congenital heart disease in fetus are genetic, infectious factors and premature birth. Congenital heart disease has a certain degree of family aggregation, so it has a certain degree of genetic predisposition, and if there is a family member with congenital heart disease in the immediate family, then the probability of the fetus suffering from the disease will be higher than normal. This may be related to chromosomal aberrations in the sperm or egg. Viral infections, especially Coxsackie virus and Rubella virus, during the development of the fetus are very likely to hinder the development of the heart in the uterine cavity, resulting in congenital heart disease. For fetuses born prematurely, as the gestational weeks are too small, the fetus’ heart is not fully developed yet, which may cause congenital heart disease with arterial ductus arteriosus. Fetuses with congenital heart disease need prompt medical treatment.