(1) Serum total triiodothyronine (TT3) and serum total thyroxine (TT4): detection of TT3 and TT4 in blood is a common indicator for determining hyperthyroidism or hypothyroidism, and also has application value for severity assessment and treatment efficacy monitoring. (2) Serum free triiodothyronine (FT3) and serum free thyroxine (FT4): FT3 and FT4 are more sensitive and meaningful than TT3 and TT4. FT3 level is important for differential diagnosis of normal, hyper or hypothyroidism, and is sensitive for the diagnosis of hyperthyroidism, and is a specific indicator for the diagnosis of T3 hyperthyroidism. FT4 measurement is an important part of routine clinical diagnosis. FT4 measurement is an important part of routine clinical diagnosis and can be used as a monitoring tool for thyroid suppression therapy. (3) Thyroid stimulating hormone (TSH): Increased TSH is seen in primary hypothyroidism, Hashimoto’s disease with hypothyroidism, exogenous thyroid stimulating hormone-secreting tumors (lung, breast), and recovery from subacute thyroiditis. When thyroid dysfunction is suspected, FT4 and TSH are often measured together, and a combination of TSH, FT3 and FT4 is often used to confirm hyperthyroidism or hypothyroidism, as well as to track the effectiveness of treatment. (4) Anti-Thyroid Peroxidase Antibody (TPOAb): Elevated TPOAb is seen in 90% of patients with chronic Hashimoto’s thyroiditis and 70% of patients with prominent goiter. It may return to normal as the disease progresses or goes into remission. If TPOAb is elevated again during remission, there is a possibility of deterioration. (5) Serum antithyroglobulin antibody (TGAb): TGAb may be elevated in 60-70% of patients with Hashimoto’s thyroiditis and primary mucinous edema, and in 20%-40% of patients with Graves’ disease. (6) Serum thyrotropin receptor antibodies (TRAb): TRAb is a group of autoantibodies against TSH receptors on the thyroid cell membrane, which are detected in the serum of 95% of Graves’ patients and help in the diagnosis and prognostic assessment of Graves’ disease.