TSH is thyrotropin, which is secreted by the pituitary gland and plays a very important role in regulating the normal function of the thyroid gland, and it is a commonly used indicator for the diagnosis of thyroid disorders in clinical practice. The normal value of TSH in adults is about 0.4-4.2uiu/ml, and the reference range varies from hospital to hospital. However, TSH fluctuates with age. For example, for infants under one year of age, the normal value is 1.7-9.1uiu/ml; for children and adolescents, it is 0.7-5.7uiu/ml; and the normal reference range for adults is between 0.4-4.2uiu/ml. A TSH value outside this range suggests the possibility of hypothyroidism and vice versa for hyperthyroidism. Further examination of thyroid ultrasound, FT3, FT4, etc. is needed to clarify the diagnosis and early treatment. Therefore, when the TSH value is abnormal, you should go to the hospital in time to see a doctor to clarify the cause of the disease and then carry out targeted treatment.