The iodine 131 treatment process is mainly divided into iodine absorption test, thyroid imaging, and treatment of thyroid disease. For iodine 131 treatment, the first step is to do iodine absorption test, the second step is to do thyroid imaging, and the last step is to do the treatment of thyroid disease. Iodine 131 treatment has the advantage of targeted treatment, high cure rate and low recurrence rate. Before the treatment, it is necessary to check the liver and kidney function, the iodine absorption rate of the thyroid gland, and then measure the amount of iodine 131 needed, and then take it orally in water according to the established dosage. After taking the medicine, it usually takes 2-3 weeks to take effect. Usually about one course of treatment. A few patients who are not cured need a second treatment. Symptoms of hypothyroidism may occur during iodine 131 treatment. After treatment, thyroid function should be checked regularly, and if there is any abnormality, patients should consult the doctor in time. It is necessary to pay attention to 131 iodine 2 hours before eating, 2 days after the treatment, it is advisable to increase the amount of drinking water, timely urination, to avoid splashing urine when defecating, rinse immediately after defecation. The above treatment should be carried out under the guidance of a doctor for better treatment of the disease.