Whether congenital hypothyroidism can be cured is something that mothers of children with congenital hypothyroidism are eager to know. Let’s start with a brief overview of some of the basics. For the sake of understanding, we will compare thyroid hormone to a product and then introduce the characteristics of this product, the production sector, the raw materials, and the coordination between the production sector and the market demand one by one. Thyroid hormone is a hormone that acts throughout the body and can affect substance metabolism, growth and development, neurodevelopment, cardiovascular system activity, and secretion of other endocrine glands in a broad and deep manner. Low thyroid hormone secretion can cause slow growth (dwarfism), poor neurodevelopment (low IQ), malnutrition, memory loss, and slow movement. The importance of thyroid hormone cannot be overstated, so where does it come from? ① Our human thyroid tissue (production department) is located at the front of the neck. The normal thyroid gland is very soft and difficult to be palpated, but it can be detected by instruments such as ultrasound. ②The main raw materials for the manufacture of this product are iodine as well as tyrosine, one cannot be missing. Finally, there is a complex regulatory system that determines the amount of production (which can be interpreted as market demand). Corresponding to the above 3 links, the etiology includes: ① destruction or absence of thyroid parenchyma (the production sector is destroyed), impaired thyroxine synthesis (there is a production sector, but lack of appropriate tools or technology), the former, such as anti-hyperthyroid drugs (inhibiting hormone synthesis) for mothers suffering from hyperthyroidism, thyroid gland underdevelopment or absence, etc.; the latter, such as impaired thyroglobulin synthesis in thyroid tissue, defective peroxidase system etc. ②Lack of raw materials, such as iodine deficiency, malnutrition, etc. (iii) non-response of thyroid tissue to regulatory systems (disconnected from market demand), such as thyroid resistance, hypothalamic-pituitary hypothyroidism, etc. If there is a problem in one of the above mentioned areas, the manifestation of “hypothyroidism” will appear. Having said that, where is the answer? The answer will be clear to all mothers with a few more pointers. The above causes, such as irreversible thyroid tissue deficiency, thyroglobulin synthesis disorder, peroxidase system defects, thyroid resistance, hypothalamic-pituitary hypothyroidism, etc., are incurable and require lifelong medication. For example, the former can be recovered after a period of separation from the mother, while the latter can be recovered by adding iodine or strengthening nutrition. It is important to emphasize that most of the children with hyperthyroidism are temporary and reversible, while those who need to take medication permanently are the minority.