Objective To study the treatment effect of 131I in nodular goiter and hyperthyroidism. Methods The thyroid nodules numbers and iodine absorption rate in 260 patients confirmed with nodular goiter and hyperthyroidism were determined, and the patients were treated with 131I and followed-up for 3 to 60 months. The patients were then given levothyroxine sodium 25 ~ 150 g/day based on their health situation to inhibit the increase TSH and hypothyroidism. Results The curative rate of hyperthyroidism with 131 I treatment was 65.39%, and partial rate was 20.0%, and hypothyroidism rate was 14.61%. After 131 I treatment, 78.85% of nodules was eliminated, nodular narrow accounted for 15.39% and nodular invalid accounted for 5.77%. The curative effect of smaller diameter nodal was better than larger ones (P < 0.05). Conclusion 131I therapy is suitable method for nodular goiter and hyperthyroidism treatment with good curative effect, especially for patients with surgery contraindication.