Congenital heart diseases constitute a heterogeneous group of malformation with various etiologies . It has generally been considered that approximately 10% of cases of CHD are genetically determined, a total of 3% are the result of environmental causes such as pollution, malnutrition male use of drugs on radiation and infectious diseased during pregnancy, early marital age and late pregnancy of women. The remaining 97% can contributed to maltifactorial mechanisms .Diagnosis and management of congenital heart diseases by using Gen Therapy. The importance of Genetic Counseling in prevention of congenital heart diseases .