Abstract: Thyroid disease during pregnancy is one of the focus of the medical profession in the field of endocrinology. Pregnant women with thyroid disease will not only face to adverse pregnancy outcomes, and it will damage the fetal brain development and lower IQ level of future generations. In order to better cope with the diagnosis and treatment of thyroid disease during pregnancy, we review the maternal thyroid function during pregnancy and changes in thyroid hormone diagnostic value affected by pregnancy, and we also offer a preliminary proposal to pregnancy diagnosis and treatment of thyroid diseases.