Thyroglobulin antibodies, or TGAb, are a common autoantibody in the serum of patients with autoimmune thyroid disease and are closely related to damage to thyroid tissue. In general, thyroglobulin antibodies should not be present in the body or only in trace amounts when the body is immunocompetent, but they are detectable in patients with non-thyroidal autoimmune diseases and in a few healthy individuals, especially in the elderly. The reference range varies according to the method of thyroglobulin antibody determination, mainly using the ECLIA method, which often results in a level of less than 115 IU/mL. Generally, laboratories only specify the upper limit of this indicator, but not the lower limit. Therefore, if the value of thyroglobulin antibody test is <10IU/mL, it indicates a negative result, which is normal and need not be too worried. If the value is greater than 115 IU/mL, it is positive and is considered more than 2 times more clinically relevant. It is usually seen in Graves' disease, Hashimoto's thyroiditis, postpartum thyroiditis, painless thyroiditis, etc. It should be combined with clinical manifestations and a series of tests such as laboratory tests, thyroid ultrasound and thyroid MRI to further clarify the cause and give appropriate treatment.