Before radioactive iodine 131 treatment of hyperthyroidism, the following preparations should be made: 1, 2~4 weeks before serving iodine-131, avoid iodine and other iodine-containing foods or drugs: kelp, seaweed, thyroxine tablets, iodine-containing contrast medium, iodine-containing multivitamins, agar, carrageenan, Lugol’s liquid, iodine-containing Chinese herbs and so on. 2, iodine-131 treatment of the condition of the former is serious, the heart rate of more than 160 beats per minute, serum T3, T4, and so on. Those who are obviously elevated should be treated with anti-thyroid drugs or cardioplegia first, and only after the symptoms have been reduced can they be treated with iodine-131; 3. Patients using anti-thyroid drugs need to stop taking them, Tabazolol stops for >3 days, and PTU needs to be stopped for >2 weeks, and then the rate of iodine-131 uptake is measured, and then the iodine-131 treatment can be used; 4. Routinely do the blood routine, blood biochemistry, blood thyroid function, thyroid ultrasound, ECG, chest X-ray and so on, Electrocardiogram, chest X-ray and other tests, women of childbearing age need to check urine HCG to rule out pregnancy, if necessary, according to the condition of the additional tests; 5, do the thyroid uptake of iodine-131 rate and thyroid ECT scanning, in order to calculate the dose of the drug; 6, a few days before and after the iodine-131, the patient should pay attention to rest, avoid strenuous activities.