ObjectiveTo summarize and analyze the possible association between thyroid diseases and alopecia areata. MethodThe literatures on the relationship between thyroid disease and alopecia areata in recent years were searched and reviewed. ResultsAmong individuals with alopecia areata, the risk of thyroid disease was heightened. They were more susceptible to autoimmune thyroid conditions, often accompanied by thyroid function abnormalities. Moreover, alopecia areata patients face an increased risk of thyroid cancer. However, in patients with thyroid disease, the change of the incidence of alopecia areata was not completely clear. The risk of alopecia areata was increased in patients with autoimmune thyroid disease, and abnormal thyroid function may be one of the potential reasons for the persistence of alopecia areata. ConclusionsAutoimmune thyroid disease and alopecia areata may have a common disease basis. Patients with alopecia areata are at greater risk of autoimmune thyroid disease and thyroid dysfunction. The increased risk of alopecia areata in patients with autoimmune thyroid disease may be related to abnormal thyroid function.