The two main types of hyperthyroidism in pregnancy are pregnancy-associated hyperthyroidism and HCG-associated hyperthyroidism. Graves’ disease is the most common cause, accounting for approximately 85% of hyperthyroidism in pregnancy. Generally, in early pregnancy, hyperthyroidism tends to worsen due to the increase in HCG levels. In the middle and late stages of pregnancy, due to the physiological immunosuppression of the body, the titer of TSH receptor-stimulating antibodies decreases and the symptoms of hyperthyroidism are easily relieved. After the end of pregnancy, the immunosuppression is lifted and most patients experience a rebound of the disease. The degree of control of hyperthyroidism directly affects the prognosis of the mother and child. Poorly controlled hyperthyroidism can lead to a high incidence of preeclampsia, miscarriage and heart failure, as well as increased fetal prematurity, low birth weight and congenital malformations, which can seriously endanger the health of the pregnant woman, fetus and newborn. The special feature of the treatment of hyperthyroidism during pregnancy is to control the excessive thyroxine while considering the effect of drugs on the fetus, to make the thyroid function of pregnant women as close as possible to or at the physiological level of normal women during pregnancy, and to avoid the occurrence of hypothyroidism. The main treatment method is antithyroid drug (ATD) therapy. The principle is that the lowest dose of antithyroid drug should be used to control the FT4 level at or slightly above the upper limit of the normal range and the serum TSH at or slightly below the lower limit of normal. Radiotherapy is contraindicated during pregnancy and the main risk of surgical treatment is preterm delivery and miscarriage. Surgical treatment is indicated if the highest dose is required continuously during pregnancy or if serious adverse effects occur, or if patient compliance is poor, or if the goiter has affected respiratory function. Regarding the use of ATD in pregnancy, the 2012 American Endocrine Society Clinical Practice Guidelines suggest that methimazole (MMI) may increase the incidence of congenital malformations in newborns in early pregnancy and recommend the use of propylthiouracil (PTU) for the treatment of hyperthyroidism. The starting dose of ATD depends on the severity of the patient’s symptoms and thyroid hormone levels. The dose of ATD should be adjusted downward after the hyperthyroidism is controlled, and the treatment should be maintained until the end of pregnancy or until delivery to avoid recurrence of hyperthyroidism. In gestational hyperthyroidism (transient thyrotoxicosis of pregnancy), the condition is associated with elevated serum HCG levels and negative autoantibodies to the thyroid gland. It usually presents as subclinical hyperthyroidism, which is self-limiting and requires only symptomatic treatment.