Iodine deficiency is a serious disease that could threaten people’s intelligence development and inhibit the economic growth in China. This paper study the long-term impact of the prevention of iodine deficiency disease in China by using the micro data of China Labor-force Dynamics Survey. The estimation result of difference-in-difference model shows that, although there’s no effect on height, the iodine supplementation campaign significantly improve individual’s education and income level. Specifically, the effect on education is generated in the stage of junior school. Besides, fetus period is found to be the most important period for iodine supplementation, and there is little effect of iodine supplementation after birth. Thus, the prevention of iodine deficiency disease promotes the accumulation of human capital and the growth of economy for China.