Congenital hypothyroidism in children, commonly known as cretinism, is a relatively common disease characterized by severe mental retardation and short stature, which seriously affects the physical and mental health of the affected children and the quality of the entire population due to its highly disabling nature and irreversible intellectual damage. According to medical statistics, the incidence of congenital hypothyroidism in all newborn children in Europe and the United States is about 1:3750; in Anhui Province, a survey of congenital hypothyroidism in newborn infants has been conducted since 2000, and according to the available information, the incidence of the disease in our province is 1:1116, and in Anqing City, a survey of this disease in newborn infants has been conducted since August 2003, and 2 new cases of congenital hypothyroidism have been found. Two cases of congenital hypothyroidism have been found (excluding the original child). The number of new births in China is about 20 million, and there are thousands of new cases every year. If we calculate the number of new births according to the natural life expectancy of 40 years, the cumulative number of patients in China is 200,000-300,000. Therefore, it is extremely important to pay attention to the early detection and treatment of this disease. The common causes of congenital hypothyroidism are mainly: congenital hypoplasia, agenesis, and ectopic thyroid gland. Since the development of the thyroid gland affects the body’s metabolism and can easily involve intelligence, low intelligence is one of the characteristics of children with hypothyroidism; followed by stunted growth and reduced basal metabolic rate. It is difficult to detect in newborns and infants, and the symptoms are not typical. Generally, there are no or little crying, exceptionally well behaved, short stature, edema, prolonged jaundice, umbilical hernia, abdominal distention, slow heart rate or low heart sound. Apathetic expressions and tongue outgrowth can be detected in early childhood, and mental retardation and short stature are particularly easy to see, but the impact on intelligence may be more severe if treatment is not started until this point of detection. In addition to the clinical symptoms mentioned above, it is important to diagnose that there are changes in thyroid function, mainly in T3, T4 and TSH. Since the presentation is atypical in newborns and infants, it is essential to carry out a screening of all newborns so that early detection and diagnosis can be made for early treatment. Treatment: Replacement of thyroxine tablets is the mainstay, and levothyroxine sodium is advocated for newborns or small infants; lifelong treatment is required except for patients with temporary hypothyroidism. Prognosis: As long as congenital hypothyroidism is treated early and for a long time, there is no effect on the child, including physical strength and intelligence, which can live and work like normal people. Therefore, it is recommended to start treatment for children with this disease within 3 months.