The problem of providing the needs of the population of Ukraine with quality drinking water in the XXI century from the actual becomes a sharp one. The question is not only the reduction of quantitative volumes unleavened water, which is threatened by a crisis of drinking water supply to certain regions of the country, and also that it is the first place to act quality of natural waters, which does not satisfy modern hygienic requirements. This is due to the increased pollution of natural water basins by industrial waste, agricultural production and municipal water consumption. In the medical and ecological-hygienic aspect, the issues of obligate contamination of water sources with global toxicants of organic and inorganic nature, disinfection of drinking and economic waters, sewage treatment, water preparation, etc. are the foremost issues. In this work, data from the State Environmental Protection Department in the Poltava region (2010 - 2017), Statistical materials of the sanitary-epidemiological situation in the water supply of the region were used. According to the Poltava regional water resources department, the river network of the Poltava region includes: one large river - the Dnieper, which flows within the region on a 145 km long section, 8 medium rivers with a total length of 1360 km (Psel, Khorol, Vorskla, Sula, Uday, Orzhitsa, Oril, Merla) and 1771 small rivers, watercourses and streams with a total length of 11501 km. The main aquifer horizons suitable for drinking use in the region are: Quaternary (alluvial) Poltava, Kharkiv, Buchak, Sineman-Lower Cretaceous and Jurassic. In total in the Poltava region there are more than 200 thousand shaft wells, which are used by about 605 thousand people (36% of the population). In 56% of wells, a significant excess of nitrate content was detected. Nitrates fall into the horizons of groundwater with human and animal waste (from non-concreted cesspools), and excessive nitrogen fertilization. In general, provision of the Poltava region with unleavened water for drinking and recreational purposes can be considered sufficient. But in relation to qualitative indicators there are problematic periods - the hot season is unfavorable for water supply of settlements on the water intake from the Dniprodzerzhynsk reservoir basin. For the population using the underground water-mountain umbrellas (upper water, Poltava and partially Kharkiv), these problem periods are spring and autumn, when there is more intense pollution of these horizons by the flow of meltwater and rainwater.