Objective To investigate the iodine nutrition status of children under 8-10 years old in Erqi District of Zhengzhou City from 2017 to 2020, and to analyze the correlation between iodine nutrition status and salt iodine. To investigate the iodine nutrition status of children 8-10 years old in Erqi District of Zhengzhou City from 2017 to 2020, and to analyze the correlation between iodine nutrition status and salt iodine.Methods A total of 800 children under 8-10 years old were selected from 9 communities in Erqi District of Zhengzhou City by stratified sampling method, and their urine iodine, salt iodine and thyroid were detected. The salt iodine content, urine iodine content and qualified rate of salt iodine in different years were analyzed, and the correlation between urine iodine and salt iodine was analyzed by Spearman rank correlation. A total of 800 children 8-10 years old were selected from 9 communities in Erqi District of Zhengzhou City by stratified sampling method, and their urine iodine, salt iodine and thyroid were detected. The salt iodine content, urine iodine content and qualified rate of salt iodine in different years were analyzed, and the correlation between urine iodine and salt iodine was analyzed by Spearman rank correlation. Results The overall median of salt iodine concentration was 26.2 mg/kg, and the total qualified rate of salt iodine was 93.00% (744/800); there were significant differences in salt iodine content and qualified rate among different years (P<0.05); the median urinary iodine content of children was 170.9 μg/L, and the difference was statistically significant among different years (P<0.05), pairwise comparison showed that the urinary iodine content in 2017 and 2018 was higher than that in 2019 (P<0.001 after correction), and that in 2020 was higher than that in 2019 (P<0.001 after correction); the urinary iodine content of 10-year-old children was higher than that of 9-year-old children, the difference was statistically significant (P<0.05); there was a positive correlation between urinary iodine and salt iodine in children (r=0.278, P<0.05); there was no significant difference in thyroid volume among different years (P>0.05); the incidence of goiter was low (2.88%), and there was no significant difference among different years (P>0.05). The overall median of salt iodine concentration was 26.2 mg/kg, and the total qualified rate of salt iodine was 93.00% (744/800); there were significant differences in salt iodine content and qualified rate among different years (P<0.05); the median urinary iodine content of children was 170.9 μg/L, and the difference was statistically significant among different years (P<0.05), pairwise comparison showed that the urinary iodine content in 2017 and 2018 was higher than that in 2019 (P<0.001 after correction), and that in 2020 was higher than that in 2019 (P<0.001 after correction); the urinary iodine content of 10-year-old children was higher than that of 9-year-old children, the difference was statistically significant (P<0.05); there was a positive correlation between urinary iodine and salt iodine in children (r=0.278, P<0.05); there was no significant difference in thyroid volume among different years (P>0.05); the incidence of goiter was low (2.88%), and there was no significant difference among different years (P>0.05).Conclusion From 2017 to 2020, the iodine nutrition status of children under 8-10 years old in Erqi District of Zhengzhou City was mostly at the appropriate level, and the salt was basically qualified iodized salt. There was a certain degree of iodine deficiency and excessive intake, and there was a positive correlation between iodine nutrition status and salt iodine. Therefore, we should strengthen the publicity and education of iodized salt related knowledge, improve the utilization rate of qualified iodized salt, and prevent the related diseases caused by iodine deficiency. From 2017 to 2020, the iodine nutritional status of children 8-10 years old in Erqi District of Zhengzhou City is mostly at the appropriate level, and the edible salt is basically qualified iodized salt. There is a certain degree of iodine deficiency and excessive intake, and there is a positive correlation between iodine nutritional status and salt iodine. Therefore, we should strengthen the propaganda and education of iodized salt related knowledge, improve the utilization rate of qualified iodized salt, and prevent the related diseases caused by iodine deficiency.