The advantages of radioactive iodine treatment for recurrent hyperthyroidism are simple, economic, high cure rate, etc. The disadvantages include causing hypothyroidism, radiothyroiditis, thyroid crisis, aggravation of active Graves’ ophthalmopathy, etc. 1. Advantages: the method is simple, economic, high cure rate, the cure rate of radioactive iodine treatment of hyperthyroidism reaches more than 85%, the symptoms are reduced in 2-4 weeks after treatment, the thyroid gland shrinks, and the thyroid function gradually returns to normal in 6-17 weeks. 2. Disadvantages (1) Hypothyroidism: It is an unavoidable result of radioactive iodine treatment. The incidence of hypothyroidism is about 5% per year, and reaches 40% to 70% in 10 years. After treatment, thyroid function should be monitored regularly, hypothyroidism should be detected as early as possible, thyroxine replacement therapy should be given in time, and medication should be taken for life. (2) Radioactive thyroiditis: It occurs 7 to 10 days after radioactive iodine treatment. In severe cases, aspirin or glucocorticoid therapy may be given. (3) Induced thyroid crisis: occurs mainly in patients with severe uncontrolled hyperthyroidism. (4) Exacerbation of active Graves’ ophthalmopathy. Patients with hyperthyroidism should go to the clinic in time and standardize the treatment under the guidance of the doctor.