Background: Iodine deficiency may result in a goiter, developmental delays and other health problems. The simplest way for the iodine deficiency prevention is consumption of iodine-rich food products. In our country, the iodine consumption is supported by edible salt iodization. Human organism excretes 80% of iodine with urine, therefore the urinary iodine level is considered as an indicator for the iodine status of an individual. Goal: The goal of our study was to evaluate a correlation between the levels of iodine in salt and in urine. Materials and Methods: 2173 samples of household salt and urine samples of 1697 school-age children were collected covering 20 aimags and Ulaanbaatar city. Levels of iodine in the salt samples were determined using a titration method, and for the determination of iodine concentrations in urine the SandellKolthoff’s reaction was used. The correlation between two sets of values was assessed with Pearson’s correlation coefficient. Results: The sample collection was organized so that the aimags were divided into 6 to 8 clusters, each cluster comprising 12 to 15 households or children. Therefore, average values of the iodine concentrations in salt and urine of each cluster were used for the correlation assessment. The result of the statistical analysis showed a high variation in correlation between salt iodine and urinary iodine at the aimag level, but the overall correlation at the country level was strong positive (r=0.7). Conclusion The hypothesis that the correlation between the iodine amount excreted by children from a certain location and the level of iodine in salt consumed by households in the same location is strong, was not confirmed at the aimag level, but the correlation was strong positive at the country level.