The syndrome of resistance to thyroid hormone(RTH) is a rare syndrome caused by the mutation of thyroid hormone receptor (TR) gene, which reduces the sensitivity of target organs to thyroid hormone (TH) and leads to the dysfunction of TH. Thyroid hormone resistance syndrome β (RTHβ) is caused by the mutations in the THRB gene. The main characteristics of RTHβ are increased thyroxine (T₄) in the circulating blood, normal or elevated levels of triiodothyronine(T₃), paired with normal or high thyroid-stimulating hormone (TSH) concentration. Clinically, it is easy to misdiagnose RTHβ as hyperthyroidism, and give anti-thyroid drugs, radioactive ¹³¹I therapy or surgery, which then leads to the aggravation of TH resistance, so the correct diagnosis of the disease is critical. In this paper, the molecular mechanism, clinical characteristics, diagnosis and treatment of RTHβ are summarized.