Modern radioecological studies to assess the effect of natural radiation on the human body have shown that at the moment of development of society, the main contribution to the exposure of the population is made by natural sources of ionizing radiation, while from 50 to 90 % of the dose load are caused by the gas radon-222 (222Rn) and daughter products of its decay. This paper presents the results of radiation-hygienic monitoring of the potentially radon-hazardous territory of the city of Baley, Trans-Baikal Territory. The measurement of the volumetric activity of radon (ОАRn) was carried out in the premises of residential and public buildings by the integral method using track exposure meters REI-4. According to the indicator of the equivalent equilibrium volumetric activity of radon (EROARn), a radiation-hygienic assessment of the premises and the calculation of potential dose loads on the population living in this territory were carried out. Studies have shown that ОАRn in residential and public buildings depends on the geological characteristics of the territory, on the design and design of buildings and structures, and on the building materials used. It was found that the main criterion for assessing the potential radon hazard of territories is the value of ОАRn in rooms on the 1st floors of buildings. According to the degree of potential radon hazard, the territory of the city of Baley can be conditionally divided into 3 types: 1 type - the territory located on a geological fault; Type 2 - the southern part of the city, represented by sedimentary rocks; Type 3 - the northern part of the city, represented by rocks of the basic gabbroid group with a low content of natural radionuclides. The types of buildings and structures and the type of building materials affect the dose load, but do not determine it. © 2021 State Research Center, Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency. All rights reserved.