Abstract: Objective To examine the prevalence,status of prevention and their change trend and influence factors of iodine deficiency disorder(IDD)among residents living in Inner Mongolia minority areas.Methods Probability sampling method was adopted for the epidemiological investigation.Goiter and urine iodine were determined among 3 963 children aged 8-10 years.Qualification rate and coverage rate of iodized salt were also determined.Results For the 2 328 table salt samples randomly collected from the producers or wholesalers,the median content of iodine was 31.4 mg/kg,with an iodized salt coverage rate of 99.59%,a qualified rate of iodized salt of 99.11%,and a consumption rate of qualified iodized salt of 98.71%.For 600 table salt samples collected randomly from households,the iodized salt coverage rate was 98.17%,the qualification rate of iodized salt was 99.32%,and the consumption rate of qualified iodized salt was 97.50%.For 864 iodized salt samples of 96 batches monthly collected from the producers,the mean content of iodine was 30.4 mg/kg,with a standard deviation of 5.02,a variable coefficient of 16.51%,and a qualification rate of 100%.The medium content of iodine was 328.3 μg/L for 400 urine samples of the children and the prevalence rate of goiter was 2.67%amang the 3 963 children.Conclusion The qualification rate,coverage rate,consumption rate of iodized salt,and the prevalence rate goiter were all up to the requirements of national standards,with a gradually improved iodine nutrition status among the residents in the areas.However,the consumption of unqualified iodized salt and non-iodized salt should be concerned.