Relevance. Mineral waters of the Tyumen deposit are unique, they highlight the features of geological formations and modern geodynamic processes. Despite the fact that mineral waters are widespread in nature, they differ in a variety of chemical, gas and isotopic composition. The work pays special attention to the hydromineral resources of the Tyumen deposit located in the Cherkashinsky and Tobolsk sites of the Tobolsk district of the Tyumen region, which can be considered as a special hydromineral area. In 2024, simultaneously with the development of the conceptual foundations for the use of thermal mineral resources in the Tyumen region, not far from Shestakov a new geothermal complex was opened. Negotiations are currently underway with potential investors to create hotel facilities with thermal waters located directly in Tobolsk. Considering the possibility of integrated use of groundwater from Mesozoic sedimentary formations in the Tobolsk region, the study of the modern chemical composition of groundwater and the assessment of the radiological environment considered in this study are of great importance. Aim. To present the results of the underground waters of the Tyumen deposit, in particular, the analysis of the chemical composition and radioactive substances of these mineral waters Cherkashinsky and Tobolsk sites of the Tyumen region. Methods. Sampling was carried out in accordance with generally accepted methods. The analysis and processing of empirical data were carried out using Microsoft Excel and Surfer programs. The geographical coordinates of the wells were documented using the GPS/GLONASS navigator in combination with the use of the Google Earth and OpenStreetMap software platforms. Results and conclusions. The development of groundwater in the Mesozoic hydrogeological basin is a multifaceted system that allows us to identify the modern characteristics of the groundwater of the Tyumen deposit. The analyzed information on the geochemical features of the study area allows us to talk about the chemical composition of the groundwater of the Tobolsk and Cherkashinsky sites. The water in the wells of the studied sites is type I sodium chloride with a total mineralization of 15.3–17.9 g/dm³, slightly alkaline (pH – 7.1–8.2), with a high content of chlorides – 9.2–10.6 g/dm³, sodium ions – 5.6–6.6 g/dm³, trace elements: bromine – 59.3–66.4, iodine – 24.1–26.7, boron – 44.0–57.5 mg/dm³. In general, the ionic composition of borehole waters is rather monotonous. According to SanPiN 2.6.1.2523-09 "Standards of radiation safety NRB-99/2009", the maximum content of 226 Ra in water is 0.68, that is, it does not exceed the standard. The level of surface radioactivity also does not exceed the permissible values.