Iodine is a biologically essential trace element that plays a significant role in the functioning of the thyroid gland. More than 80 % of Mongolia's population suffers iodine deficiency. The aim of this study is to study the effects of stable iodine in natural waters and rocks and soils with geochemical features of the local landscape, on the morbidity of residents with endemic goiter and other non-malignant diseases. In the summer of 2015 samples from water, soils and cut grasses were taken in order to determine the iodine content. It is proven that there is no direct relationship between the numbers of disease incidents with percentage covered with iodine prevention.