Congenital heart disease is the abbreviation of congenital heart disease (CHD), which refers to congenital malformations caused by abnormal development of the heart and large blood vessels during fetal life, and is the most common heart disease in children. According to the proportion, about 100,000 to 150,000 newborns with congenital heart disease are born in China every year, and about 1/3 of them die within one month after birth due to serious and complicated malformations if they are not treated. If any factor affects the development of the heart during the fetal heart development stage, it may lead to congenital heart disease. The cause of the vast majority of patients with congenital heart disease is currently unknown. It is currently believed that the development of congenital heart disease may be the result of an interaction between the fetal surroundings and genetic factors. The etiology of congenital heart disease can be broadly divided into intrinsic and extrinsic factors. Intrinsic factors are mainly related to genetic factors, which can be caused by chromosomal inheritance and gene mutations, and genes associated with the formation of different types of cardiovascular malformations have been found on different chromosomes. Children with a family history of congenital heart disease have a significantly higher chance of developing congenital heart disease. The more important external factors of congenital heart disease are intrauterine infections, especially viral infections during the mother’s pregnancy, such as rubella, influenza, coxsackievirus infection, and metabolic diseases, such as diabetes, hypercalcemia, phenylketonuria, and intrauterine hypoxia, which may be associated with the development. Therefore, good maternal health care especially early pregnancy with appropriate amount of folic acid supplementation and active prevention of rubella, influenza and other viral diseases are of positive significance in the prevention of congenital heart disease. However, what signs and symptoms in children should be highly alert for congenital heart disease? If your child has recurrent respiratory infections, no weight gain, hoarse voice, shallow breathing, feeding difficulties, easy sweating, purple and black lips and nails found when crying, squatting symptoms, i.e., often squatting voluntarily for a moment when walking or playing, or even sudden fainting and convulsions for unknown reasons when crying or active. Please go to the hospital immediately for a comprehensive examination when the above situation occurs, so as not to delay the condition and miss the best time for surgery.