Thyroglobulin antibody, known in English as Tg-Ab, is a common autoantibody in the serum of patients with autoimmune thyroid disease. It is of clinical value in the regression and treatment of thyroiditis, especially Hashimoto’s thyroiditis. Higher antibodies suggest further medical attention. Serum Tg-Ab is a specific indicator for the diagnosis of thyroid autoimmune diseases and is strongly positive in 80% to 90% of patients with chronic thyroiditis and 60% of patients with hyperthyroidism. Transient hypothyroidism, which occurs during treatment of hyperthyroidism, is strongly associated with Tg-Ab. Tg-Ab can be used as a differential diagnostic indicator for goiter, and a positive test is usually considered for chronic lymphocytic thyroiditis rather than for goiter. It is recommended to consult the endocrinology department of a regular hospital if an elevated level of thyroglobulin antibodies is found.