Chemical composition of soils is influenced by both natural phenomena, such as destruction of rocks and man-made factors associated with disposal of oil waste and ore processing plants. The relevance of the discussed issue is caused by the data about the impact of area of residence on development of diabetes, as well as the prevalence of the disease. A great variety of geological structures (platform foredeep, folded region) and rocks (sedimentary, volcanic, igneous, metamorphic rocks of different composition, structure and age) on the territory of the Republic of Bashkortostan determines the regional characteristics of microelement profile of the biosphere, the region can be used as a unique scientific testing ground to study the medical and biological role of geological factors. The main aim of the research is to study the effect of geological factors and features of microelement composition of terrain on development of diabetes. The methods used in the study. The authors have used the results of soil testing for the content of 45 chemical elements in different geological areas, estimated the prevalence of diabetes in the Republic of Bashkortostan according to the data of the diabetes register for 2010-2014 depending on geological conditions of the area; plot the prevalence map using the program ArcGIS 10.2, the method of classification is «natural breaks». The results. The paper demonstrates the consistency of the regional geological conditions with the features of the elemental composition of terrain and the prevalence of diabetes. The areas of carbonate rocks and the increased concentration of tectonic dislocations are associated with increase in the iron and beryllium content in the soil and decrease of the disease prevalence. The territory with the rocks of continental origin is characterized by the decrease in iron and beryllium level in the soil and relative increase in the prevalence of diabetes.