Hypothyroidism caused by Hashimoto’s thyroiditis is a relatively common clinical condition, which is not serious and is relatively simple to treat, as patients can take oral replacement therapy with Eugenol. The specific dosage of Eugenol should be decided by a specialist endocrinologist according to the level of thyroid hormones, and Eugenol should be taken orally once a day, half an hour before meals. When the thyroid function is completely normalized by Eugenol, the patient can take it orally at the same dose, and the thyroid function will be checked once every six months to a year. Patients with Hashimoto’s hypothyroidism need to take oral replacement therapy with Eugenol for life and cannot stop taking it.