Hashimoto's thyroiditis is an autoimmune inflammatory thyroid disease caused by the diffuse enlargement of thyroid follicular cells, and may present with transient hyperthyroidism during different clinical stages. During the period of normal thyroid function as well as the eventual phase of reduced thyroid function, appropriate anti-hyperthyroidism medications can be administered symptomatically when the patient is clinically hyperthyroid. When the patient is hypothyroid, it is necessary to timely supplement with thyroid hormones for treatment, and it is essential to dynamically monitor the individual’s thyroid hormone levels, thyroid hormone antibodies, and thyroid ultrasound to make a comprehensive assessment. It is always important to maintain a low iodine diet and avoid consuming foods that are high in iodine.